Smart hazard detector providing follow up communications to detection events

ABSTRACT

Ambient amount of a hazardous condition may be monitored. A mode may be set to a state indicative of the hazardous condition being present in the ambient environment. It may then be determined that the amount of the hazard in the ambient environment has dropped below an alarm criterion. A time period may then be tracked during which the amount of the hazardous condition present in the ambient environment of the hazard detector has remained below the alarm criterion. It may be determined that the time period has reached at least a threshold duration, during such time period the amount of the hazardous condition present in the ambient environment of the hazard detector having remained below the alarm criterion. An indication of the hazardous condition easing may be output in response to the time period being at least the threshold duration.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/617,619, filed Feb. 9, 2015, entitled “Smart-Home Hazard DetectorProviding Useful Follow Up Communications To Detection Events,” now U.S.Pat. No. 9,189,946, issued Nov. 17, 2015 which is a continuation of U.S.patent application Ser. No. 14/508,146, filed Oct. 7, 2014, entitled“Smart-Home Hazard Detector Providing Useful Follow Up Communications ToDetection Events,” now U.S. Pat. No. 8,988,232, issued Mar. 24, 2015,which claims priority to U.S. Provisional Application No. 61/887,969,filed Oct. 7, 2013, entitled “User-Friendly Detection Unit,” and claimspriority to U.S. Provisional Application No. 61/887,963, filed Oct. 7,2013 which are each hereby incorporated by reference for all purposes.

BACKGROUND

A conventional smoke or carbon monoxide alarm likely provides noindication that a hazardous condition is present until a loud alarm issounded. Such an arrangement may be annoying to a user when the alarmhas been triggered accidentally. For example, a small amount of smokegenerated by cooking may be enough to trigger a smoke alarm to sound.The user may then have to remedy the condition that caused the alarm byairing out the room in which the smoke alarm is located to clear thesmoke and/or by actuating a button on the alarm to silence it. Further,the user may be left guessing as to whether the remediation actionsbeing taken by the user are sufficient to alleviate the conditions thatinitially triggered the alarm to sound.

FIELD

This document relates to systems, devices, methods, and related computerprogram products for smart buildings including the smart home. Moreparticularly, this patent specification relates to detection units, suchas hazard detection units (e.g., smoke detectors. carbon monoxidesensors, etc.) or other monitoring devices, that are useful in smartbuilding and smart home environments.

SUMMARY

Methods, systems, devices, apparatuses, and processor-readable mediumsare presented for alerting users to easing hazardous conditions. Once athreshold level of a hazardous condition has been realized (e.g., smoke,carbon monoxide), a hazard detector may monitor for the hazardouscondition to drop below a (same or different) threshold level. Once thedrop occurs an amount of time may be waited. Once a defined time periodhas elapsed and the hazard condition has not risen above a thresholdlevel, an indication may be output that indicates the hazardouscondition is easing. The defined time period may be based on variousfactors, including the type of hazard, readings from other hazarddetectors, and/or a measured humidity level to name only a few examples.

In some embodiments, a method for detecting that a hazardous conditionis easing is presented. The method may include measuring, by a hazarddetector, a first amount of the hazardous condition present in anambient environment of the hazard detector. The method may includesetting, by the hazard detector, a mode of the hazard detector to astate indicative of the hazardous condition being present in the ambientenvironment of the hazard detector. The method may include measuring, bya hazard detector, a second amount of the hazardous condition present inthe ambient environment of the hazard detector, the second amount of thehazardous condition being less than the first amount of the hazardouscondition. The method may include determining, by the hazard detector,that the second amount of the hazardous condition present in the ambientenvironment of the hazard detector is below a threshold hazardouscondition level while the mode of the hazard detector is set to thestate indicative of the hazardous condition being present. The methodmay include tracking, by the hazard detector, a time period during whichthe amount of the hazardous condition present in the ambient environmentof the hazard detector has remained below the threshold hazardouscondition level while the mode of the hazard detector is set to thestate indicative of the hazardous condition being present. The methodmay include determining, by the hazard detector, that the time periodhas reached at least a threshold duration, during such time period theamount of the hazardous condition present in the ambient environment ofthe hazard detector having remained below the threshold hazardouscondition level while the mode of the hazard detector is set to thestate indicative of the hazardous condition being present. The methodmay include outputting, by the hazard detector, an indication of thehazardous condition easing in response to the time period being at leastthe threshold duration.

Such embodiments may include one or more of the following features: Anauditory indication may be output that comprises a spoken messageindicative of the hazardous condition easing. The spoken messageindicative of the hazardous condition easing may include a spokenindication of a name of a room in which the hazardous condition iseasing. The method may include setting, by the hazard detector, the modeof the hazard detector to a second state indicative of the hazardouscondition not being present in the ambient environment of the hazarddetector in response to determining that the time period has reached atleast the threshold duration. The method may include determining, by thehazard detector, the threshold duration based on a type of the hazardouscondition. The hazardous condition may be selected from the groupconsisting of: smoke and carbon monoxide. The threshold duration mayvary based on whether the hazardous condition is smoke or carbonmonoxide. The method may include determining, by the hazard detector,one or more event characteristics of the hazardous condition. The methodmay include determining, by the hazard detector, the threshold durationbased on the one or more event characteristics of the hazardouscondition. The method may include receiving, by the hazard detector,from one or more hazard detectors located in other rooms of a structurein which the hazard detector is installed, information indicative of thehazardous condition. The method may include determining, by the hazarddetector, the threshold duration based on the received informationindicative of the hazardous condition from the one or more hazarddetectors located in other rooms of the structure in which the hazarddetector is installed. The method may include measuring, by the hazarddetector, a humidity level in the ambient environment of the hazarddetector. The method may include determining, by the hazard detector,the threshold duration based on the measured humidity level. The methodmay include sounding, by the hazard detector, an auditory alarm,indicative of the hazardous condition being present in the ambientenvironment of the hazard detector.

In some embodiments, a non-transitory processor-readable medium for ahazard detector is presented. The medium may include processor-readableinstructions configured to cause one or more processors of the hazarddetector to perform any or all of the above steps detailed in relationto the methods.

In some embodiments, a hazard detector is presented. The hazard detectormay include a hazard sensor that measures amounts of a hazardouscondition present in an ambient environment of the hazard detector. Thehazard detector may include an output device that outputs informationinto the ambient environment of the hazard detector. The hazard detectormay include a processing system that comprises one or more processors,the processing system being in communication with the output device andthe hazard sensor. The processing system may be configured to receive afirst measurement of the first amount of the hazard present in theambient environment of the hazard detector. The processing system may beconfigured to set a mode of the hazard detector to a state indicative ofa hazardous condition being present in the ambient environment of thehazard detector. The processing system may be configured to receive asecond measurement of a second amount of the hazardous condition presentin the ambient environment of the hazard detector, the second amount ofthe hazardous condition being less than the first amount of thehazardous condition. The processing system may be configured todetermine that the second amount of the hazardous condition present inthe ambient environment of the hazard detector is below a thresholdhazardous condition level while the mode of the hazard detector is setto the state indicative of the hazardous condition being present. Theprocessing system may be configured to track a time period during whichthe amount of the hazardous condition present in the ambient environmentof the hazard detector has remained below the threshold hazardouscondition level while the mode of the hazard detector is set to thestate indicative of the hazardous condition being present. Theprocessing system may be configured to determine that the time periodhas reached at least a threshold duration, during such time period theamount of the hazardous condition present in the ambient environment ofthe hazard detector having remained below the threshold hazardouscondition level while the mode of the hazard detector is set to thestate indicative of the hazardous condition being present. Theprocessing system may be configured to cause the output device to outputan indication of the hazardous condition easing in response to the timeperiod being at least the threshold duration.

In some embodiments, a hazard detector apparatus is presented. Theapparatus may include means for measuring a first amount of thehazardous condition present in an ambient environment of the hazarddetector. The apparatus may include means for setting, a mode of thehazard detector to a state indicative of the hazardous condition beingpresent in the ambient environment of the hazard detector. The apparatusmay include means for measuring a second amount of the hazardouscondition present in the ambient environment of the hazard detector, thesecond amount of the hazardous condition being less than the firstamount of the hazardous condition. The apparatus may include means fordetermining that the second amount of the hazardous condition present inthe ambient environment of the hazard detector apparatus is below athreshold hazardous condition level while the mode of the hazarddetector is set to the state indicative of the hazardous condition beingpresent. The apparatus may include means for tracking a time periodduring which the amount of the hazardous condition present in theambient environment of the hazard detector apparatus has remained belowthe threshold hazardous condition level while the mode of the hazarddetector is set to the state indicative of the hazardous condition beingpresent. The apparatus may include means for determining that the timeperiod has reached at least a threshold duration, during such timeperiod the amount of the hazardous condition present in the ambientenvironment of the hazard detector having remained below the thresholdhazardous condition level while the mode of the hazard detector is setto the state indicative of the hazardous condition being present. Theapparatus may include means for outputting an indication of thehazardous condition easing in response to the time period being at leastthe threshold duration.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of variousembodiments may be realized by reference to the following figures. Inthe appended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 illustrates an embodiment of a hazard detector for detecting aneasing of a hazardous condition.

FIG. 2 illustrates an embodiment of another hazard detector fordetecting an easing of a hazardous condition.

FIGS. 3A, 3B, and 3C illustrate embodiments of various state flows of ahazard detector that detects an easing of a hazardous condition.

FIG. 4 illustrates an embodiment of a method for detecting an easing ofa hazardous condition.

FIG. 5 illustrates an embodiment of a method for detecting an easing ofa hazardous condition that varies a time period used in determining whento make an announcement indicating that the hazardous condition haseased.

FIG. 6 illustrates an embodiment of a method for determining a thresholdduration value to use in assessing whether a hazardous condition haseased.

FIG. 7 illustrates an embodiment of a method for using a pre-alarm stateof a hazard detector to alert a user to the presence and easing of ahazardous condition.

FIG. 8 illustrates an example of a smart-home environment within whichone or more hazard devices can be installed.

FIG. 9 illustrates a network-level view of the extensible devices andservices platform with which a hazard detector may be integrated.

FIG. 10 illustrates an embodiment of an abstracted functional view ofthe extensible devices and services platform of FIG. 9, with referenceto a processing engine as well as devices of the smart-home environment.

FIG. 11 illustrates an embodiment of a computer system.

FIGS. 12-18 represent various illumination states and audio messagesthat may be output by a hazard detector.

FIG. 19 illustrates a chart indicative of various situations in whichpre-alert messages and sounds may be silenced and situations in whichmessages and sounds cannot be silenced.

FIG. 20 illustrates an exemplary situation of when a heads-up(pre-alert) state is used prior to an alarm (emergency) state.

DETAILED DESCRIPTION

Conventional hazard alarms typically make a loud noise when a hazardouscondition, such as smoke or carbon monoxide, is detected. Oftentimes,the hazardous condition is not dangerous enough for a user to abandonthe structure. Rather, the user may take steps to ameliorate thehazardous condition. For instance, if the user burned food on a stove,the user may open a window and turn on a fan or wave a towel tocirculate air. As another example, if a small fire has started, the usermay douse it with water. A conventional hazard alarm may continue makingnoise until the hazardous condition is no longer detected or the userpushes a button on the alarm to silence the alarm.

Rather than having a hazard detector have only binary states (i.e.,alarm on or off), embodiments detailed herein describe hazard detectorsthat can inform users of not only when a hazardous condition is present,but when that hazardous condition is rising and/or easing. Suchinformation may be useful to a user in deciding whether to evacuate astructure and/or in determining if steps the user has taken toameliorate the hazard are helping to dissipate the hazardous condition.

When embodiments of a hazard detector as detailed herein make anannouncement (which may involve sound and/or light) as to a hazardouscondition easing, various factors may be evaluated to determine whensuch an announcement should be made, including: the type of hazard, thehumidity, characteristics of the detected hazard, and/or the number ofhazard detectors that have detected the hazardous condition. Otherfactors are also possible. Based on such factors, the hazard detectormay determine if the hazard has been easing for a sufficient period oftime to announce that the hazardous condition appears to be decreasingor has dissipated completed.

Further, the ability to inform a user that a hazardous condition iseasing may be used in conjunction with a multi-state hazard detector.Rather than having the hazard detector have only two alarm states, suchas alarm and non-alarm, a hazard detector may have three or more states:non-alarm (in which the hazard detector monitors the ambient environmentfor hazards), pre-alarm (the hazard detector detects a small amount of ahazard, the amount of the hazard being insufficient to sound the fullalarm), and alarm (the hazard detector's alarm sounding for a greateramount of the hazard being detected). Such a pre-alarm state may informa user that the alarm is going to sound soon if the hazardous conditionkeeps getting worse. Such a pre-alarm state may allow a user time toameliorate the hazardous condition before having a full alarm sound.When the state of the hazard detector is downgraded, an announcement asto the easing of the hazardous condition may be made.

FIG. 1 illustrates an embodiment of a hazard detector 100 that candetect an easing of a hazardous condition. Hazard detector 100 mayinclude: processing system 110, hazard sensor 120, and output device130. Processing system 110 may include one or more processors thatexecute various modules. Such modules may be implemented using softwareor firmware. Alternatively, such modules may be implemented directly asspecial-purpose hardware. Processing system 110 may include twoprocessors. One processor may serve as a low-level processor thathandles safety-critical tasks, such as receiving data from hazard sensor120 and sounding an alarm when the hazard reaches a threshold amount.Another processor may serve as a high-level processor that handlesusability functionality, such as providing a user with spoken messages,detecting gestures, and communicating with a wireless network. Theseprocessors may communicate with each other and other components ofhazard detector 100 to function as processing system 110. In someembodiments, the low-level processor may be capable of functioningindependently of the high-level processor. For example, if thehigh-level processor becomes non-functional, the low-level processor maystill be able to sound an alarm if a hazard is detected.

Hazard sensor 120 may detect one or more types of hazards. Hazard sensor120 may detect smoke (as a signal that fire is present) or carbonmonoxide, as two examples. Hazard sensor 120 may provide processingsystem 110 with an indication of an amount of a hazard detected in theambient environment of hazard detector 100. Processing system 110 may beconfigured to analyze the indication of the amount of the hazarddetected by hazard sensor 120.

Hazard monitor engine 112 of processing system 110 may receiveindications of the amount of a hazard detected in the ambientenvironment of hazard detector 100 from hazard sensor 120. Hazarddetector 100 may be configured to be set into multiple states, such asdetailed in relation to FIGS. 3A-3C. Based upon the comparison to one ormore threshold values, hazard monitor engine 112 may provide input tostate engine 111, which may track which state hazard detector 100 iscurrently in. For instance, when a first threshold value is exceeded,state engine 111 may be set to a pre-alarm state. If a second thresholdvalue of detected hazard is exceeded, state engine 111 may be set to analarm state.

Hazard monitor engine 112 and state engine 111 may be in communicationwith messaging engine 113. Messaging engine 113 may determine one ormore auditory and/or visual messages to be output to a user based uponinput from state engine 111 and/or hazard monitor engine 112. Forinstance, when messaging engine 113 determines that the state of hazarddetector 100 has entered a pre-alarm state, messaging engine 113 maycause output device 130 to provide an auditory and/or visual indicationto a user that the amount of a hazard in the environment is rising. Whenmessaging engine 113 determines that the state of hazard detector 100has exited an alarm state or a pre-alarm state, messaging engine 113 maycause output device 130 to provide an auditory and/or visualannouncement to a user that the amount of a hazard in the environment iseasing.

Output device 130 may be configured to output light or sound into theambient environment of the hazard detector. Output device 130 may be aspeaker that is capable of outputting human speech. Output device 130may alternatively be one or more lights that can output one or morecolors and one or more animation patterns. In some embodiments, multipleoutput devices are present, such as to output light and sound toindicate a pre-alarm state, an alarm state, and/or when a hazardouscondition has eased.

FIG. 1 illustrates a simplified embodiment of hazard detector 100. Itshould be understood that multiple hazard sensors and/or multiple outputdevices may be present in other embodiments. For example, FIG. 2illustrates an embodiment of hazard detector 200 for detecting an easingof a hazardous condition. Hazard detector 200 represents a more detailedembodiment that includes a greater number of components and modules. Inhazard detector 200, various components may be present including:processing system 110, light sensor 255, light 245, carbon monoxidesensor 121, smoke sensor 122, battery-based power source 210, wirelesscommunication module 230, user input component 222, structure powersource 220, presence detector 250, microphone 260, audio output device240, humidity sensor 241, and temperature sensor 265.

Processing system 110 of hazard detector 200 may include multiplesubmodules. Such submodules may be implemented using hardware, firmware,and/or software that is executed by underlying hardware, such as one ormore processors. Such modules may include: state engine 111, hazardmonitor engine 112, messaging engine 113, hazard thresholds 114, timeperiod monitor 115, and time period decision data 116. For instance,such modules may represent code that is executed by a high-levelprocessor and/or a low-level of hazard detector 200.

Hazard monitor engine 112 may receive indications of the amount of ahazard detected in the ambient environment of hazard detector 200 fromcarbon monoxide sensor 121 and smoke sensor 122. State engine 111 ofhazard detector 200 may be configured to be set into multiple states,such as detailed in relation to FIGS. 3A-3C. Based upon the comparisonto one or more threshold values from hazard thresholds 114, hazardmonitor engine 112 may provide input to state engine 111 and/ormessaging engine 113.

Hazard monitor engine 112 and state engine 111 may be in communicationwith messaging engine 113. Messaging engine 113 may determine one ormore auditory and/or visual messages to be output to a user based uponinput from state engine 111 and/or hazard monitor engine 112. Forinstance, when messaging engine 113 determines that the state of hazarddetector 100 has entered a pre-alarm state, messaging engine 113 maycause output device 130 to provide an auditory and/or visual indicationto a user that the amount of a hazard in the environment is rising. Whenmessaging engine 113 determines that the state of hazard detector 100has exited an alarm state or a pre-alarm state, messaging engine 113 maycause output device 130 to provide an auditory and/or visual indicationto a user that the amount of a hazard in the environment is easing.

Hazard monitor engine 112 may compare the received levels of a hazard tothreshold values of stored hazard thresholds 114. A first thresholdvalue may be defined to determine when state engine 111 should be placedinto a pre-alarm mode. A second threshold value may be defined todetermine when state engine 111 should be placed into an alarm mode. Athird threshold value may be defined to determine when state engine 111should be returned from the alarm mode to the pre-alarm mode or to anon-alarm mode and/or to determine when the hazardous condition iseasing. Such thresholds present in hazard thresholds 114 may be selectedbased on the type of hazard and/or other conditions.

Time period monitor 115 may be used in conjunction with hazard monitorengine 112 to determine when the state maintained by state engine 111should be decreased from an alarm mode to a pre-alarm mode or to anon-alarm mode and/or when an announcement should be made that thehazardous condition is easing. For instance, it may be required that theamount of the hazard detected in the environment of hazard detector 200remain below a threshold amount stored by hazard thresholds 114 for atleast a period of time before the state of the hazard detector isdowngraded. The period of time may vary based on multiple factors, suchas the type of hazard, the number of hazard detectors that detected thehazard, characteristics of the hazard, and/or humidity level detected byhazard detector 200. Time period monitor 115 may monitor an amount oftime for which the detected hazard level as received by hazard monitorengine 112 has remained below a threshold defined in stored hazardthresholds 114. Time period monitor 115 may also determine the durationof the period of time by accessing time period decision data 116 andassessing one or more factors associated with the hazard. For instance,time period monitor 115 may retrieve a predefined duration for theperiod of time from time period decision data 116 based on the type ofhazard. This predefined duration may be adjusted based on variousparameters such as the humidity level in the ambient environment ofhazard detector 200. Time period decision data 116 may containindications of how the period of time should be lengthened if the hazardhas been detected by multiple hazard detectors located within astructure in which hazard detector 200 is installed. Further, timeperiod decision data 116 may store information indicative of how longthe detected level of hazard is required to be below the threshold valuebased on characteristics of the detected hazard. For instance, the levelof detected hazard having increased rapidly may result in a differentperiod of time than if the level of detected hazard increased slowly.Based upon analyzing the detected level of hazard in the environment andtime period decision data 116, time period monitor 115 may determinewhen state engine 111 should downgrade its state from alarm orpre-alarm. Messaging engine 113 may output an indication that thehazardous condition is easing based upon the state of state engine 111being downgraded or time period monitor 115 directly informing messagingengine 113 that an indication of the condition easing should be output.

Light sensor 255 detects the presence of light in the ambientenvironment of hazard detector 100. Light sensor 255 may detect abrightness level in the ambient environment of hazard detector 200. Sucha brightness level may be affected by natural and artificial lighting.Light sensor 255 may provide an indication of the brightness level inthe ambient environment of hazard detector 200 to processing system 110.Light 245 may represent a light integrated into hazard detector 200 thatoutputs light to the external environment around hazard detector 200.Light 245 may be controlled by processing system 110. Light 245 mayinclude one or more lighting elements, such as light emitting diodes(LEDs). Light 245 may be capable of outputting various illuminationmodes that can include: multiple colors, multiple animation patterns,and/or such multiple animation patterns at varying speeds. The at leastone color, animation pattern, and speed of animation output by light 245may be determined based on a determination performed by processingsystem 110. Therefore, based on conditions monitored by processingsystem 110, light 245 may be illuminated or disabled. When light 245 isilluminated, the one or more colors, animation pattern, and/or speed ofthe animation output by light 245 may vary based on a determinationperformed by processing system 110.

Presence detector 250 may detect a presence or motion within the ambientenvironment of hazard detector 200. Presence detector 250 may includeone or more passive infrared (PIR) sensors and/or ultrasonic sensorsthat receive infrared radiation (or reflected ultrasonic sound) from theambient environment of the hazard detector. For instance, a user walkingor otherwise moving in the vicinity of hazard detector 200 emitsinfrared radiation which may be detected by presence detector 250. Inother embodiments, presence detector 250 may use some other form ofsensor than a PIR sensor. Presence detector 250 may provide anindication to processing system 110 of when motion is present in theambient environment of hazard detector 200. More generally, presencedetector 250 may be a form of sensor that can detect a user's presenceeven if motionless. In some embodiments, presence detector 250 outputsraw data that is analyzed by processing system 110 to determine ifmotion is present or a user is otherwise present. In some embodiments,motion may be analyzed to determine if it likely corresponds to a personor is incidental (e.g., a pet, an object being warmed by sunlight,etc.).

In hazard detector 200, two hazard sensors are present: carbon monoxidesensor 121 and smoke sensor 122. In some embodiments, multiple versionsof each of these types of sensors can be present. For instance, anionization and a photoelectric smoke sensor may be present in hazarddetector 200. When carbon monoxide sensor 121 senses carbon monoxide orsmoke sensor 122 senses smoke, indication may be sent to a processor ofprocessing system 110. An indication of an alarm condition may betransmitted to a low-level processor that triggers an alarm to soundand/or a light color and/or animation to be output by light 245. Thislow-level processor may trigger light 245 directly to illuminate in astate indicative of a hazard or may provide input to a high-levelprocessor that is part of processing system 110 that triggers a lookupof an illumination definition to determine an appropriate color,animation, and/or speed of animation to use for illumination of light245. Regardless of whether the high-level or low-level processor isused, a different color, animation, and/or speed may be used for carbonmonoxide as compared to smoke. In some embodiments, both the low andhigh level processors are capable of causing light 245 to illuminate.

Wireless communication module 230 may allow processing system 110 tocommunicate with a wireless network present within the structure inwhich hazard detector 200 is installed. For instance, wirelesscommunication module 230 may communicate with a wireless network thatuses the IEEE 802.11a/b/g network protocol standard for communication.Wireless communication module 230 may permit processing system 110 tocommunicate with a remote server, which may be maintained by amanufacturer of hazard detector 200 or by a third-party. The remoteserver may be configured to provide information to processing system 110about an account of a user associated with hazard detector 200. Forinstance, if an account of the user maintained at the remote serverrequires attention from a user, such indication may be provided toprocessing system 110 via wireless communication module 230. Suchindication may be provided by the remote server in response to inquiryfrom processing system 110 made to the remote server. Further,processing system 110 may transmit status information to a remoteserver. Such an arrangement may permit a user to view status informationabout the hazard detector by logging in to the remote server via acomputing device and accessing the user account.

Wireless communication module 230 may also permit direct connection witha wireless computerized device. For instance, wireless communicationmodule 230 may create a wireless area network (e.g., WiFi network) thata computerized wireless device, such as a tablet computer or smartphone,can connect with. Once connected, messages may be exchanged betweenprocessing system 110 (via wireless communication module 230) and awireless computerized device, such as to permit an initial configurationof hazard detector 200 to be performed via the computerized wirelessdevice. In other embodiments, such an initial configuration is performedvia a network connection through a router or other form of directcommunication, such as Bluetooth® or WiFi Direct®.

Wireless communication module 230 may also allow for communication withone or more other hazard detectors installed within the same structureas hazard detector 200. For instance, hazard detectors may be installedwithin various rooms within a structure. Each hazard detector may storean indication of the type of room it is installed within. These hazarddetectors may be configured to alert each other when a hazard isdetected. As such, while a hazard may be detected by another hazarddetector, hazard detector 200 may alert a user to the presence of thehazard in the other room. When a hazard is present, hazard detector 200may receive indications from other hazard detectors indicative ofwhether that hazard detector is also sensing the hazard. Hazarddetectors that are not sensing the hazard may not provide such anindication or may transmit a message indicative of the hazard not beingdetected.

User input component 222 may represent a component that receives inputthat can be passed to processing system 110. User input component 222may take the form of a button or switch on hazard detector 200. Bydepressing the button or otherwise actuating user input component 222, auser can provide input via user input component 222 to processing system110. For instance, user input component 222 may be used by a user todisable an alarm being sounded by hazard detector 200. User inputcomponent 222 may be encircled or have its perimeter otherwise outlinedby light 245 (that is, by the light itself and/or by light output bylight 140). Therefore, when light 245 is active, and the user desires toprovide input (e.g., to silence an alarm), the user may touch or pushhazard detector 200 within the area defined by light 245 and/or thelight output by light 245.

Hazard detector 200 may include battery-based power source 210 andstructure power source 220. Structure power source 220 may be used topower hazard detector 200 when such power is available. Structure powersource 220 may represent a hard-wired connection within a structure(e.g., house, building, office, etc.) that provides an AC or DC power toone or more hazard detectors located throughout the structure. While theAC or DC power may be available a significant percentage of time (e.g.,99.5% of the time), it may be desirable for hazard detector 200 tocontinue functioning if structure power is unavailable (e.g., during apower failure). As such, battery-based power source 210 may also bepresent. Battery-based power source 210 may include one or morebatteries which power the various components of hazard detector 200 whenstructure power source 220 is not available. In some embodiments ofhazard detector 200, structure power source 220 is not present and/orthe hazard detector may not be capable of connected with structure powersource 220. As such, hazard detector 200 may permanently rely onbattery-based power source 210 to power components of hazard detector200. Structure power source 220 and battery-based power source 210 areillustrated in FIG. 2 as connected with processing system 110. It shouldbe understood that, while structure power source 220 and battery-basedpower source 210 are illustrated as only connected with processingsystem 110, this is for simplicity of illustration only; structure powersource 220 and/or battery-based power source 210 may be connected to thevarious components of hazard detector 200 as necessary to power suchcomponents.

Audio output device 240 and light 245 may represent different forms ofoutput device 130 of hazard detector 100. Audio output device 240 may bea speaker that is configured to output sound. Audio output device 240may be capable of outputting synthesized or recorded speech, thusallowing spoken messages to be output to users in the vicinity of hazarddetector 200. Audio output device 240 may receive vocal messages to beoutput from messaging engine 113. Other sounds, such as an alarm buzzingor ringing may also be generated by audio output device 240. Audiooutput device 240 may include a piezo sound generator configured togenerate a very loud alarm sound.

Humidity sensor 241 may detect humidity level in the ambient environmentof hazard detector 200. An indication of the detected humidity level maybe provided to processing system 110. This humidity level may be used todetermine the time period for which the detected level of hazard isrequired to be below a threshold value before the state of hazarddetector 200 is downgraded and/or an announcement is made that thehazardous condition has eased. Microphone 260 may be used to detectsound the vicinity of hazard detector 200. For instance, spoken commandsby user may be received by microphone 260 and processed by processingsystem 110.

Temperature sensor 265 may be used by hazard detector 200 to monitor theambient temperature of hazard detector 200. Temperature measurementsmade by temperature sensor 265 may be used in controlling when HVACsystems are turned on or off.

FIGS. 3A, 3B, and 3C illustrate embodiments of various state flows of ahazard detector that detects an easing of a hazardous condition. Stateflows 300A, 300B, and 300C may be implemented on hazard detector 100,hazard detector 200, or some other embodiment of a hazard detector. FIG.3A illustrates a state flow 300A of a hazard detector that has twostates: non-alarm state 301 and alarm state 302. Non-alarm state 301 mayalso be referred to as a standby or monitor mode. In non-alarm state301, the presence of a hazard may be monitored for. In non-alarm state301, no alarm may be sounded nor may a light be illuminated to beindicative of an alarm. In alarm state 302, an auditory and/or visualalarm may be sounded and/or illuminated, respectively, by the hazarddetector. The level of hazard detected in the environment of the hazarddetector may continue to be monitored. If the level decreases below adefined threshold amount, flow 310 may be followed to downgrade thestate of the hazard detector back to the non-alarm state 301.

Flow 310 occurring may result in the hazard detector outputting anindication that the hazardous condition is easing. In some embodiments,in addition to the level of detected hazard falling below a threshold,the level of detected hazard may be required to remain below thethreshold for predefined period of time, which may vary based on severalfactors, before flow 310 is followed and then indication of thehazardous condition easing being output by the hazard detector. In someembodiments, flow 310 results in a synthesized spoken message beingoutput by hazard detector that indicates, for example: “[Type of Hazard]is easing.” The [Type of Hazard] may vary based on if smoke or carbonmonoxide was detected. As another example, the hazard detector mayindicate the room in which the hazard detector is located. For example,the hazard detector may output: “[Type of Hazard] is easing in the[room].” A user may have previously provided the hazard detector withroom designation in which the hazard detector is installed, such as abedroom, kitchen, bathroom, etc.

FIG. 3B illustrates a state flow 300B of a hazard detector that hasthree states: non-alarm state 301, alarm state 302, and pre-alarm state303. Generally, pre-alarm states and alarm states can be referred to asstates indicative of a presence of a hazardous condition (albeit indifferent amounts). In non-alarm state 301, the presence of a hazard maybe monitored for. In non-alarm state 301, no alarm may be sounded normay a light be illuminated to be indicative of an alarm. If an amount ofhazard is detected that exceeds a first threshold, the state of thehazard detector is upgraded to pre-alarm state 303. In pre-alarm state303, the full alarm of the hazard detector may not sound. However, amessage, such as a spoken message, may be output to a user thatindicates that a level of hazard in the environment has risen or isrising. In some embodiments, recommendations may be made to the user asto how to deal with the rising level of the hazard. In some embodiments,a light of the hazard detector may be illuminated to indicate thepre-alarm state.

If the level of hazard detected in the ambient environment of the hazarddetector decreases, such as below the first threshold amount or belowsome other defined threshold amount, flow 312 may be followed todowngrade the state of the hazard detector from pre-alarm state 303 tonon-alarm state 301. Flow 312 may result in a message being output bythe hazard detector that is indicative of the hazardous conditioneasing. If the level of hazard detected in the ambient environment ofthe hazard detector increases, such as above a second threshold amount(greater than the first threshold amount), pre-alarm state 303 may beupgraded to alarm state 302. In alarm state 302, an auditory and/orvisual alarm may be sounded and/or illuminated, respectively, by thehazard detector. The amount of hazard detected in the environment of thehazard detector may continue to be monitored.

If the amount of hazard decreases below the second threshold amount (orsome other defined threshold amount), flow 313 may be followed todowngrade the state of the hazard detector back to pre-alarm state 303.Alternatively, flow 311 may be followed to downgrade the state of thehazard detector from alarm state 302 to non-alarm state 301. Based oneither flow 311 or flow 313 occurring, the message may be output by thehazard detector that indicates that the hazard condition is easing.Whether flow 313 or 311 is followed may depend on how much the level ofdetected hazard has fallen in the ambient environment of the hazarddetector. In some embodiments, only flows 312 and 313 are available fordowngrading the state of the hazard detector. In other embodiments, onlyflows 311 and 312 are available for downgrading the state of the hazarddetector. A message being output to a user indicative of the hazardouscondition easing may be assigned to any or all of flows 311, 312, 313.For instance, for flow 313, a message may indicate that the hazardouscondition has started to ease, while a message for flow 312 may indicatethat the hazardous condition has eased further.

As with state flow 300A, in addition to the detected level of hazardbeing required to fall below one or more threshold amounts in order forthe state of the hazard detector to be downgraded, the detected level ofhazard may be required to stay below the threshold amount for at least aperiod of time prior to the state of the hazard detector beingdowngraded. This period of time may be determined based on one or morefactors, as discussed in relation to method 600 of FIG. 6.

FIG. 3C illustrates a state flow 300C of a hazard detector that has fourstates: non-alarm state 301, alarm state 302, first pre-alarm state 304,and second pre-alarm state 305. In non-alarm state 301, the presence ofhazards may be monitored for. In non-alarm state 301, no alarm may besounded nor may a light be illuminated to be indicative of an alarm. Ifan amount of hazard is detected that exceeds a first threshold, thestate of the hazard detector is upgraded to first pre-alarm state 304.In first pre-alarm state 304, the full alarm of the hazard detector maynot sound nor be lit. However, a message, such as a spoken message, maybe output to a user that indicates that a level of hazard in theenvironment is rising. In some embodiments, recommendations may be madeto the user as to how to deal with the rising level of the hazard. Insome embodiments, a light of the hazard detector may be illuminated toindicate the first pre-alarm state 304.

If the level of hazard detected in the ambient environment of the hazarddetector decreases, such as below the first threshold amount or belowsome other defined threshold amount, flow 315 may be followed todowngrade the state of the hazard detector from first pre-alarm state304 to non-alarm state 301. Flow 315 may result in a message beingoutput by the hazard detector that is indicative of the hazardouscondition easing. If the level of hazard detected in the ambientenvironment of the hazard detector increases, such as above a secondthreshold amount, first pre-alarm state 304 may be upgraded to secondpre-alarm state 305. In second pre-alarm state 305, the full alarm ofthe hazard detector may still not sound nor be lit. However, a message,such as a spoken synthesized or recorded message, may be output to auser that indicates that a level of hazard in the environment is stillrising. This message may be more urgent than the message associated withfirst pre-alarm state 304. In some embodiments, recommendations may bemade to the user as to how to deal with the continued rising level ofthe hazard. In some embodiments, a light of the hazard detector may beilluminated to indicate the second pre-alarm state 305.

If the detected hazard level increases above a third threshold amount,second pre-alarm state 305 may be upgraded to alarm state 306. In alarmstate 302, an auditory and/or visual alarm may be sounded and/orilluminated, respectively, by the hazard detector. The level of hazarddetected in the environment of the hazard detector may continue to bemonitored.

Flows 314, 315, 316, 317, 318, and 319 represent various flows of astate of the hazard detector being downgraded. In some embodiments, whenthe detected level of a hazard drops below a threshold value, the hazarddetector may be downgraded to the non-alarm state 301. In otherembodiments, the hazard detector may downgrade its state through one ormore pre-alarm states based on the detected hazard level being less thanone or more threshold amounts. For instance, as the detected hazardlevel in the ambient environment of the hazard detector decreases, alarmstate 306 may be downgraded to second pre-alarm state 305 according toflow 317, second pre-alarm state 305 may be downgraded to firstpre-alarm state 304 following flow 316 and first pre-alarm state 304 maybe downgraded to non-alarm state 301 via flow 315. Further, depending onthe detected level of hazard, various states may be skipped. Forinstance, alarm state 306 may be downgraded to first pre-alarm state 304via flow 318. Similarly, second pre-alarm state 305 may be downgraded tonon-alarm state 301 via flow 319. Alarm state 306 may also be downgradeddirectly to non-alarm state 301 via flow 314.

The threshold values used to determine when to downgrade states of thehazard detector may be the same threshold values used to determine whenstates of the hazard detector are upgraded. For instance, a samethreshold value may be used to determine when first pre-alarm state 304should be upgraded to second pre-alarm state 305, as when secondpre-alarm state 305 should be downgraded to first pre-alarm state 304.Alternatively, the thresholds used for upgrading and downgrading statesmay vary from each other. For instance, a first threshold value may beused to determine when first pre-alarm state 304 should be upgraded tosecond pre-alarm state 305, but a second threshold (smaller in magnitudethan the first) may be used to determine when second pre-alarm state 305should be downgraded to first pre-alarm state 304.

A message being output to indicate that a hazardous condition is easingmay be associated with all or any of flows 314, 315, 316, 317, 318, and319. In some embodiments, it may be desirable for only one easingmessage to be output, such as when the state of the hazard detectorsdowngraded to non-alarm state 301. In other embodiments, it may bedesirable to indicate that the hazardous condition has started to ease,such as at flow 316 or flow 317 and later be followed by another messageindicating that the hazardous condition has further eased such as atflow 315.

As with state flows 300A and 300B, in addition to the detected level ofhazard being required to fall below one or more threshold amounts inorder for the state of the hazard detector to be downgraded, thedetected level of hazard may be required to stay below the thresholdamount for at least a period of time prior to the state of the hazarddetector being downgraded. This period of time may be determined basedon one or more factors, as discussed in relation to method 600 of FIG.6.

While not illustrated in FIG. 3C, or any of the other state flows, itmay be possible for a state to be upgraded and skip one or more otherstates. For instance, if a high enough level of a hazard is detected,non-alarm state 301 may be upgraded directly to alarm state 306. Stateflows 300A, 300B, and 300C focus on hazard detectors that have two,three, and four states respectively. It should be understood that inother embodiments, a greater number of states may also be possible. Insome embodiments, hazard detectors may have a different number of statesdepending on the type of hazard detected. For instance, state flow 300Amay be used for when carbon monoxide is detected while state flow 300Bor 300C may be used for when smoke is detected.

Various methods may be performed by a hazard detector using the statesdetailed in relation to FIGS. 3A-3C. FIG. 4 illustrates an embodiment ofa method 400 for detecting an easing of a hazardous condition. Method400 may be performed using hazard detector 100, hazard detector 200, orsome other embodiment of a hazard detector. Each step of method 400 maygenerally be performed by a hazard detector. Throughout method 400, oneor more sensors of the hazard detector may continue to monitor for andmeasure amounts of hazardous conditions, such as smoke and/or carbonmonoxide, in the ambient environment of the hazard detector.

At step 405, a hazardous condition may be determined to be present inthe environment of a hazard detector. Such a determination may be madebased on one or more measured amounts of the hazardous condition beingcompared to a stored threshold value. The hazard may involve thepresence of smoke, which can be indicative of fire, carbon monoxide, orsome other condition or compound that is potentially dangerous tooccupants present in the structure in which the hazard detector isinstalled. At step 405, the hazard detector may be receivingmeasurements of the amount of detected hazard in the environment of thehazard detector from one or more sensors of the hazard detector. Inresponse to the threshold value being exceeded by the measured amount ofthe hazardous condition, method 400 may proceed to step 410. Otherwise,if no amount of the hazardous condition is measured by the hazarddetector, the hazard detector may continue to monitor for such ahazardous condition until one is detected.

At step 410, a state of the hazard detector may be set to be indicativeof the hazardous condition being present. Referring back to FIGS. 3A-3C,step 410 may involve the hazard detector being set from a non-alarmstate to either a pre-alarm state or an alarm state. In indication ofthe current state of the hazard detector may be stored by the processingsystem of the hazard detector, such as to a non-transitory storagemedium associated with a state engine. While step 410, and later stepsof method 400, are being performed, the hazard detector may continue tomonitor for hazards in the ambient environment of the hazard detector.

At step 415, the hazard detector may determine that the amount of thehazardous condition in the ambient environment is now below a thresholdvalue. This determination may be based on one or more measurements ofhazard level made after step 405 was performed. Therefore, the amount ofhazardous condition in the environment of the hazard detector may havedecreased since step 405. The threshold used at step 405 to determinethat the hazardous condition is present in the ambient environment ofthe hazard detector may be the same threshold amount used in theanalysis of step 415. Alternatively, the threshold values used maydiffer. For example, the threshold amount used at step 415 may besmaller in magnitude than the threshold amount used to determine thatthe hazardous condition was present at step 405.

At step 420, following the amount of the hazardous condition being belowthe threshold, a period of time for which measurements of the hazardouscondition has remained below the threshold value may be tracked. If theamount of hazard detected in the ambient environment of the hazarddetector exceeds the threshold, the time period may be reset.

Whether an alarm of the hazard detector is sounding during steps 415 and420 may be dependent on whether the state set at step 410 was apre-alarm state or an alarm state. If an alarm state, one or moreauditory and/or visual alarms may be output by the hazard detector whilesteps 415 and 420 are being performed. If a pre-alarm state, the hazarddetector may be taking no action or may be outputting a warning(pre-alarm message) indicative of the hazard detector being in thepre-alarm state. If a warning (pre-alarm message) is output in thepre-alarm state, the warning will likely be less loud and/or intrusiveto a user than auditory and/or visual outputs by the hazard detector inthe alarm state. For instance, the warning (pre-alarm message) may be aspoken message that states: “Warning, the hazard level is rising.”

At step 425, it may be determined that the period of time which wastracked at step 420 has reached at least a threshold duration. Thethreshold duration may be stored by the hazard detector. For instance,the threshold duration may be based on the type of hazard. If smoke wasdetermined to be present at step 405, a first threshold duration may beused. If carbon monoxide was determined to be present at step 405, asecond threshold duration may be used instead. In some embodiments,rather than a stored threshold duration being defined, the hazarddetector may calculate or otherwise modify the threshold duration basedon one or more factors, at least some of which are discussed in relationto FIG. 6.

At step 430, the hazard detector may output one or more indications ofthe hazardous condition easing. The output of step 430 may be performedin response to the period of time being determined to have reached thethreshold duration of step 425. The indications of the hazardouscondition easing may include: an auditory message, which may include aspoken message, and a visual indication, such as a light of the hazarddetector illuminating a color that is not typically associated with ahazard, such as green or blue. Additionally, in response to the periodof time having reached at least the threshold duration of step 425, thestate of the hazard detector may be downgraded such as in accordancewith the embodiments of FIGS. 3A-3C. For example, from an alarm state,the hazard detector may be downgraded to either a non-alarm state orpre-alarm state. If the hazard detector was set to a pre-alarm state atstep 410, the hazard detector may be set to a non-alarm state. Further,it is possible in some embodiments that a period of time does not needto be evaluated before an easing announcement is output—rather, theeasing announcement is output in response to the level of detectedhazard dropping below a threshold amount only.

FIG. 5 illustrates an embodiment of a method 500 for detecting an easingof a hazardous condition that varies a time period used in determiningwhen the hazardous condition has eased. Method 500 may be performedusing hazard detector 100, hazard detector 200, or some other embodimentof a hazard detector. Method 500 may represent a more detailedembodiment of method 400. Each step of method 500 may generally beperformed by a hazard detector. Throughout method 500, one or moresensors of the hazard detector may continue to monitor for and measureamounts of hazardous conditions, such as smoke and/or carbon monoxide,in the ambient environment of the hazard detector. At step 501, theambient environment of the hazard detector may be monitored for hazards.At this time, the hazard detector may be set to a non-alarm state. Thehazard detector may monitor for one or multiple types of hazards,including smoke and carbon monoxide. It should be understood thatthroughout method 500, sensors of the hazard detector may continue tomeasure levels of hazardous conditions, if any, present in the ambientenvironment of the hazard detector. For instance, referring to hazarddetector 200, carbon monoxide sensor 121 and smoke sensor 122 mayprovide hazard measurements to processing system 110 for analysis.

At step 505, a hazardous condition may be determined to be present inthe environment of a hazard detector. Such a determination may be madebased on one or more measured levels of a hazardous condition beingcompared to a stored threshold value. The hazard may involve thepresence of smoke, which can be indicative of fire, carbon monoxide, orsome other condition or compound that is potentially dangerous tooccupants present in the structure in which the hazard detector isinstalled. At step 505, the hazard detector may be receivingmeasurements of the amount of detected hazard in the environment of thehazard detector from one or more sensors of the hazard detector.

At step 510, a state of the hazard detector may be set to be indicativeof the hazardous condition being present. Referring back to FIGS. 3A-3C,step 510 may involve the hazard detector being set from a non-alarmstate to either a pre-alarm state or an alarm state. An indication ofthe current state of the hazard detector may be stored by the processingsystem of the hazard detector, such as to a non-transitory storagemedium. While step 510, and later steps of method 500 are beingperformed, the hazard detector may continue to monitor for hazards inthe ambient environment of the hazard detector. At step 510, dependingon the state of the hazard detector, the hazard detector may beoutputting one or more visual and/or auditory indications. If the hazarddetector is in a pre-alarm state, the hazard detector may output awarning that the amount of hazard in the ambient environment of thehazard detector is rising and illuminate a light to be indicative of thepre-alarm state. If the hazard detector is in the alarm mode the hazarddetector may sound the alarm and illuminate a light to be indicative ofthe alarm state.

At step 515, while continuing to monitor the amount of the hazardouscondition in the ambient environment of the hazard detector, the hazarddetector may determine that the amount of the hazardous condition in theambient environment is now below a stored, threshold value. Thisdetermination may be based on one or more measurements of hazard levelmade after step 505 was performed. Therefore, the amount of thehazardous condition in the ambient environment of the hazard detectormay have decreased since step 505. The first threshold value used atstep 505 to determine that the hazardous condition was present in theambient environment of the hazard detector may be the same storedthreshold value used in the determination of step 515. Alternatively,the two threshold values may be different. For example, the thresholdvalue used at step 515 may be smaller in magnitude than the thresholdvalue used to determine that the hazardous condition was present at step505.

At step 520, in response to the amount of the hazardous condition beingdetermined to be below the stored threshold value, a period of time forwhich measurements of the hazardous condition have remained below thethreshold value may be tracked. If the amount of hazard detected in theambient environment of the hazard detector exceeds a threshold value(which could be the threshold used at step 515 or 505), the time periodmay be reset/restarted and/or additional steps may be taken, such assounding an alarm or making an announcement that the amount of hazard inthe environment is rising.

At step 525, a threshold duration may be determined based on one or morefactors. The threshold duration may be determined using: the type ofhazard detected, the number of hazard detectors that have detected thehazard, the state of the hazard detector, characteristics of the hazard,and/or a measured humidity level in the ambient environment of thehazard detector. The hazard detector may have stored data indicative ofhow a threshold duration should be determined in view of such factors.Further detail regarding how the threshold duration can be determined ispresented in relation to method 600 of FIG. 6. It should be understoodthat rather than being performed following step 520, step 525 may alsobe performed at some time prior to step 520.

At step 530, it may be determined that the period of time which wastracked at step 520 has reached at least the threshold durationdetermined at step 530. The period of time may cease being tracked oncestep 530 is performed. In response to step 530, step 535 may beperformed.

At step 535, the hazard detector may output one or more indications ofthe hazardous condition easing in response to step 530 being performed.The indications of the hazardous condition easing may include: anauditory message, which may include a synthesized or recorded spokenmessage, and/or a visual indication, such as a light of the hazarddetector illuminating a color that is not typically associated with ahazard, such as green or blue.

At step 540, in response to the period of time having reached at leastthe threshold duration of step 530 and/or step 535 having beenperformed, the state of the hazard detector may be downgraded such as inaccordance with the embodiments of FIGS. 3A-3C. For example, from analarm state, the hazard detector may be set to either a non-alarm stateor a type of pre-alarm state. If the hazard detector was set to apre-alarm state at step 510, the hazard detector may be set to anon-alarm state. Method 500 may then return to step 501 to monitor forhazards. If the hazard detector is to be set to a pre-alarm state froman alarm state (or other pre-alarm state), such as flows 313, 316, 317,or 318 of FIGS. 3B and 3C, method 500 may follow the dotted path andperform step 510 in lieu of step 540. At step 510, the state of thehazard detector may be set to the downgraded state of a pre-alarmcondition. A different threshold amount may be used for the evaluationof step 515 when performing method 500 again. Further, the thresholdduration may be determined to have a different duration based on thecurrent state of the hazard detector.

FIG. 6 illustrates an embodiment of a method 600 for determining athreshold duration value to use in assessing whether a hazardouscondition has eased. Method 600 may be performed as part of method 400,method 500, or as part of some other method. For instance, method 600may be performed as part of step 525 of method 500. Each step of method600 may generally be performed by a hazard detector. Throughout method600, one or more sensors of the hazard detector may continue to monitorfor and measure amounts of hazardous conditions, such as smoke and/orcarbon monoxide, in the ambient environment of the hazard detector.Various factors may be used to determine the duration of the thresholdused in determining when the hazard detector should inform user that thehazardous condition is easing. The various determinations performed aspart of method 600 may be performed in a varying order. As such, method600 represents a possible embodiment with various other embodimentsbeing possible.

At step 605, a type of hazard detected may be determined. For eachparticular type of hazard, a default or minimum threshold duration valuemay be stored by (or be otherwise accessible to) the hazard detector.For instance, a fire/smoke hazard may be associated with a firstduration while a carbon monoxide hazard may be associated with a second,different duration. The type of hazard may be determined based on, forexample, the type of hazard that exceeded the threshold of step 505 ofmethod 500. In some embodiments, if multiple hazards are present, athird threshold duration may be selected.

At step 610, an amount of ambient humidity may be determined using oneor more humidity sensors of the hazard detector. For instance, humiditysensor 241 of hazard detector 200 may be used to determine the ambienthumidity level. The humidity level may be assessed for a current valueand/or to determine whether the humidity level is rising or falling. Thehazard detector may store a table or other data storage arrangement thatrelates ranges of humidity levels to an indication of the thresholdduration. For instance, the hazard detector may store a table or otherdata storage arrangement that indicates that if the detected humiditylevel is between 10%-20%, the threshold duration may be increased by oneminute. In some embodiments, an algorithm is stored to calculate how thethreshold duration should be set based on the detected humidity level.The threshold duration may also be set or adjusted based on whether theambient humidity level is rising or falling. While step 610 is focusedon humidity, it should be understood that temperature may beadditionally or alternatively used in determining the thresholdduration. Additionally or alternatively, carbon monoxide levels may bemeasured. The level of detected carbon monoxide may be used to adjustthe threshold duration (and/or a level of sensitivity to smoke).

At step 615, the hazard detector, via a wireless or wired communicationmodule, may receive one or more indications of other hazard detectorslocated within the same structure as the hazard detector indicative ofwhether the same (or different) hazard is being detected in thoselocations. If a hazard is detected in multiple locations within astructure, such as in different rooms, it may be indicative that thehazardous condition is widespread in the structure and may be morelikely to be a significant safety concern. The hazard detector mayreceive signals from other hazard detectors that indicates whether ornot a hazard has been detected by such other hazard detectors. In someembodiments, the hazard detector may store indications of the locationsand/or numbers of hazard detectors that are installed within the samestructure as the hazard detector. If no indication is received from suchhazard detectors, it may be assumed that such hazard detectors are notsensing the presence of the hazard. In some embodiments, the hazarddetector may poll other hazard detectors to determine levels of thehazardous condition in other locations within the structure. Thepresence of multiple different types of hazards within the structure mayalso be determined by the hazard detector by receiving data from otherhazard detectors. The threshold duration may be set or adjusted based onin which other locations the hazard was detected, the level of thehazard detected in other locations, and/or at how many hazard detectorsthe hazard was detected. In some embodiments, an easing message may notbe output by the hazard detector until the hazard level remains belowthe threshold amount for at least the threshold duration at every hazarddetector within the structure in which the hazard detector is installed.

At step 620, characteristics of the hazardous condition may beevaluated. These characteristics may be used to set or adjust thethreshold duration. For instance, characteristics of the hazardouscondition may involve a determination of the rapidity with which theamount of the hazard increased in the ambient environment of the hazarddetector (e.g., slow, smoldering fire or fast, smoky fire), the maximumamount of the hazardous condition detected, the mean/media amount of thehazardous condition detected, other hazardous conditions detected duringthe same time period, the amount of time for which the hazardouscondition has been detected, etc. In some embodiments, the hazardouscondition may be compared to stored profiles of various types ofhazardous conditions, such as grease fires, electrical fires, furnacecarbon monoxide leakage, etc., to classify the hazardous condition. Theprofile selected and/or the characteristics analyzed may be used to setor adjust the threshold duration.

At step 625, at least some of the factors determined in relation tosteps 605-through 620, and possibly additional factors, may be used indetermining the threshold duration. In some embodiments, a defaultthreshold duration is used as a starting point and is then adjustedbased on the factors at step 625. For instance, the presence of a factor(e.g., two other hazard detectors having detected the hazard) mayinvolve the threshold duration being increased by a predefined amount oftime, such as three minutes. Such adjustments that can be implementedbased on such factors may be stored by the hazard detector, such as inthe form of a look-up table. In some embodiments, an algorithm may takeeach of the determined factors into account to calculate a thresholdduration. The longer the duration, the longer the amount of time thatmust elapse with the amount of hazard remaining below the thresholdvalue before the hazard detector outputs an indication that the amountof the hazard in the environment of the hazard detector is easing.

FIG. 7 illustrates an embodiment of a method 700 for using a pre-alarmstate of a hazard detector to alert a user to the presence and easing ofa hazardous condition. Method 700 may be performed using hazard detector100, hazard detector 200, or some other embodiment of a hazard detector.Method 500 may represent a more detailed embodiment of method 400 and/ormethod 500. Each step of method 700 may generally be performed by ahazard detector. Throughout method 700, one or more sensors of thehazard detector may continue to monitor for and measure amounts ofhazardous conditions, such as smoke and/or carbon monoxide, in theambient environment of the hazard detector.

At step 705, the ambient environment of the hazard detector may bemonitored for hazards. At this step, the hazard detector may be set to anon-alarm state. The hazard detector may monitor for multiple types ofhazards, including smoke and carbon monoxide. It should be understoodthat throughout method 700, one or more sensors of the hazard detectormay continue to monitor for levels of hazards, if any, present in theambient environment of the hazard detector. For instance, referring tohazard detector 200, carbon monoxide sensor 121 and smoke sensor 122 mayprovide hazard measurements to processing system 110 for analysis.

At step 710, it may be determined if a hazardous condition is present inthe environment of a hazard detector. Such a determination may be madebased on one or more measured levels of a hazardous condition beingcompared to a stored threshold value. The hazard may involve thepresence of smoke, which can be indicative of fire, carbon monoxide, orsome other condition or compound that is potentially dangerous tooccupants present in the structure in which the hazard detector isinstalled. Referring to hazard detector 200 of FIG. 2 for example,hazard monitor engine 112 may determine that a hazard is present bycomparing a measured value from either carbon monoxide sensor 121 orsmoke sensor 122 to a corresponding threshold value from hazardthresholds 114. If the measured hazardous condition meets and/or exceedsa first threshold value, method 700 may proceed to step 715; otherwisethe hazard detector continues to monitor for hazardous conditions atstep 705.

At step 715, a state of the hazard detector may be set to be indicativeof the hazardous condition being present. Referring back to FIGS. 3A-3C,step 715 may involve the hazard detector being set from a non-alarmstate to a pre-alarm state. An indication of the current state of thehazard detector may be stored by the processing system of the hazarddetector, such as to a non-transitory storage medium. While step 715 isbeing performed, and later steps of method 500 are being performed, thehazard detector may continue to monitor for hazards in the ambientenvironment of the hazard detector. Referring to hazard detector 200 ofFIG. 2 for example, state engine 111 may have its state set to apre-alarm state (e.g., a first pre-alarm state, a second pre-alarmstate).

At step 720, the hazard detector may be outputting one or more visualand/or auditory indications. The hazard detector has been set to apre-alarm state based on the detected hazard level of step 710, thehazard detector may output an auditory warning, which may include amessage containing speech, stating that the amount of hazard in theambient environment of the hazard detector is rising and illuminate alight to be indicative of the pre-alarm state. For example, such a lightmay be illuminated using a color typically associated with a problem orhazard, such as yellow or red.

The hazard detector may continue to monitor the hazard level in theambient environment of the hazard detector at step 722. The hazarddetector may monitor the level of detected hazard to determine if itexceeds a second threshold value (which is representative of a greateramount of the hazard being present than the first threshold value usedat step 710) or if the amount of hazard falls below a third thresholdvalue, which may match the first threshold value or may be a smaller inmagnitude than the first threshold value. If the amount of hazardremains between the second and third threshold value, method 700 mayremain at step 722 until one of the threshold values is met. Referringto FIG. 3B, the hazard detector may be in pre-alarm state 303. If thesecond threshold is exceeded, the state of the hazard detector willtransition to alarm state 302. If the third threshold is met, the stateof the hazard detector may transition to non-alarm state 301 (followingone or more other conditions being met).

If the hazardous condition worsens at step 722 and the level of hazarddetected by the hazard detector exceeds the second threshold value,method 700 may proceed to step 725. At step 725, a state of the hazarddetector may be set to an alarm state. An indication of the alarm stateof the hazard detector may be stored by the processing system of thehazard detector, such as to a non-transitory storage medium. At step 730and auditory and/or a visual alarm may be output to alert the user tothe alarm state. The hazard detector may output an alarm sound and/or anauditory message, which may include speech, stating that the amount ofhazard in the ambient environment of the hazard detector is dangerousand illuminate a light to be indicative of the alarm state. For example,such a light may be illuminated a color typically associated with aproblem or hazard, such as yellow or red. An animation indicative of theseverity of the hazard may also be output, such as by flashing the lightrapidly.

At step 735, after the auditory and/or visual alarm has been soundingfor a period of time, the hazard detector may determine that thehazardous condition has decreased below the third threshold value. Inresponse to the hazardous level decreased below the third thresholdvalue, method 700 may proceed to step 740. Returning to step 722, if isdetermined that the hazardous condition meets or falls below the thirdthreshold value, method 700 may proceed to step 740 without performingsteps 725 through 735. As such, at the start of step 740, the hazarddetector may be set to either a pre-alarm state or an alarm state.

At step 740, in response to the amount of the hazardous condition beingdetermined to be below the third threshold value, a period of time forwhich measurements of the hazardous condition have remained below thethreshold value may be tracked. For instance, a counter of the hazarddetector may be initiated or a timestamp may be created. If the amountof hazard detected in the ambient environment of the hazard detectorexceeds the third threshold value again, the time period may be resetand/or additional steps may be taken, such as sounding an alarm ormaking an announcement that the amount of hazard in the environment isrising or returning to step 722 or step 715.

At step 745, a threshold duration may be determined based on one or morefactors. The threshold duration may be determined using: the type ofhazard detected, the number of hazard detectors that have detected thehazard, the state of the hazard detector, characteristics of the hazard,and/or a measured humidity level in the ambient environment of thehazard detector. The hazard detector may have stored data indicative ofhow a threshold duration should be determined in view of such factors.Further detail regarding how the threshold duration can be determined ispresented in relation to method 600 of FIG. 6. It should be understoodthat rather than being performed following step 740, step 745 may alsobe performed at some time prior to step 740.

At step 750, it may be determined that the period of time which wasstarted to be tracked at step 740 has reached at least the thresholdduration determined at step 745. The period of time may cease beingtracked once step 750 is performed (e.g., a counter may be disabled). Inresponse to step 750, step 755 may be performed.

At step 755, the hazard detector may output one or more indications ofthe hazardous condition easing in response to step 750 being performed.The indications of the hazardous condition easing may include: anauditory message, which may include a synthesized or recorded spokenmessage, and/or a visual indication, such as a light of the hazarddetector illuminating a color that is not typically associated with ahazard, such as green or blue. If a spoken message is output, themessage may indicate in which room the hazard detector is located. Forinstance, the message may be: “[Hazard] is clearing in the [room].”Where [hazard] is the type of hazard (smoke, carbon monoxide, etc.) and[room] is the room that was designated as the location in which thehazard detector was installed by a user during a set up process. In someembodiments, the hazard detector may communicate that the hazardouscondition is easing to the other hazard detectors located within thesame structure as in which the hazard detector is installed. Step 755may further include a chime or other sound being output to signal thatthe hazard is clear. In some embodiment a light pattern, such as a pulseof green light is output by the hazard detector to be indicative of thehazard clearing. The auditory and/or visual message may then be outputthrough such other hazard detectors installed within the structure.

At step 760, the state of the hazard detector may be downgraded such asin accordance with the embodiments of FIGS. 3A-3C such as to a non-alarmstate. Method 700 may then return to step 705 to monitor for hazards inthe non-alarm state. In the non-alarm state, the hazard detector may notbe outputting any visual and/or auditory warnings regarding hazardousconditions.

Method 700 is focused on a single pre-alarm state being used, however,it should be understood that method 700 may be applied to embodimentsthat have multiple pre-alarm states, such as state flow 300C of FIG. 3C.For instance, between steps 720 and 722, an additional iteration ofsteps 722 through 730 may be added to evaluate a second pre-alarm stateand output a warning corresponding to the second pre-alarm state (e.g.,more urgent than a first pre-alarm state but less urgent than an alarmstate). Such a second pre-alarm state may use a fourth threshold value,different than the first threshold value, to evaluate if the hazarddetector has entered into the second pre-alarm state. The second andthird thresholds may still be used to determine if the hazard detectorshould enter an alarm state (the hazardous condition worsens) orindicate that the hazardous condition is easing and return to either alower pre-alarm state or the non-alarm state.

Hazard detectors, as detailed herein, may be installed in a smart-homeenvironment. FIG. 8 illustrates an example of a smart-home environment800 within which one or more of the devices, methods, systems, services,and/or computer program products described further herein can beapplicable. The depicted smart-home environment 800 includes a structure850, which can include, e.g., a house, office building, garage, ormobile home. It will be appreciated that devices can also be integratedinto a smart-home environment 800 that does not include an entirestructure 850, such as an apartment, condominium, or office space.Further, the smart home environment can control and/or be coupled todevices outside of the actual structure 850. Indeed, several devices inthe smart home environment need not physically be within the structure850 at all. For example, a device controlling a pool heater orirrigation system can be located outside of the structure 850.

The depicted structure 850 includes a plurality of rooms 852, separatedat least partly from each other via walls 854. The walls 854 can includeinterior walls or exterior walls. Each room can further include a floor856 and a ceiling 858. Devices can be mounted on, integrated with and/orsupported by a wall 854, floor 856 or ceiling 858.

In some embodiments, the smart-home environment 800 of FIG. 8 includes aplurality of devices, including intelligent, multi-sensing,network-connected devices, that can integrate seamlessly with each otherand/or with a central server or a cloud-computing system to provide anyof a variety of useful smart-home objectives. The smart-home environment800 may include one or more intelligent, multi-sensing,network-connected thermostats 802 (hereinafter referred to as smartthermostats 802), one or more intelligent, network-connected, hazarddetectors 804, and one or more intelligent, multi-sensing,network-connected entryway interface devices 806 (hereinafter referredto as “smart doorbells 806”). According to embodiments, the smartthermostat 802 detects ambient climate characteristics (e.g.,temperature and/or humidity) and controls a HVAC system 803 accordingly.The hazard detector 804 may detect the presence of a hazardous substanceor a substance indicative of a hazardous substance (e.g., smoke, fire,or carbon monoxide). The smart doorbell 806 may detect a person'sapproach to or departure from a location (e.g., an outer door), controldoorbell functionality, announce a person's approach or departure viaaudio or visual means, or control settings on a security system (e.g.,to activate or deactivate the security system when occupants go andcome).

In some embodiments, the smart-home environment 800 of FIG. 8 furtherincludes one or more intelligent, multi-sensing, network-connected wallswitches 808 (hereinafter referred to as “smart wall switches 808”),along with one or more intelligent, multi-sensing, network-connectedwall plug interfaces 810 (hereinafter referred to as “smart wall plugs810”). The smart wall switches 808 may detect ambient lightingconditions, detect room-occupancy states, and control a power and/or dimstate of one or more lights. In some instances, smart wall switches 808may also control a power state or speed of a fan, such as a ceiling fan.The smart wall plugs 810 may detect occupancy of a room or enclosure andcontrol supply of power to one or more wall plugs (e.g., such that poweris not supplied to the plug if nobody is at home).

Still further, in some embodiments, the smart-home environment 800 ofFIG. 8 includes a plurality of intelligent, multi-sensing,network-connected appliances 812 (hereinafter referred to as “smartappliances 812”), such as refrigerators, stoves and/or ovens,televisions, washers, dryers, lights, stereos, intercom systems,garage-door openers, floor fans, ceiling fans, wall air conditioners,pool heaters, irrigation systems, security systems, and so forth.According to embodiments, the network-connected appliances 812 are madecompatible with the smart-home environment by cooperating with therespective manufacturers of the appliances. For example, the appliancescan be space heaters, window AC units, motorized duct vents, etc. Whenplugged in, an appliance can announce itself to the smart-home network,such as by indicating what type of appliance it is, and it canautomatically integrate with the controls of the smart-home. Suchcommunication by the appliance to the smart home can be facilitated byany wired or wireless communication protocols known by those havingordinary skill in the art. The smart home also can include a variety ofnon-communicating legacy appliances 840, such as old conventionalwasher/dryers, refrigerators, and the like which can be controlled,albeit coarsely (ON/OFF), by virtue of the smart wall plugs 810. Thesmart-home environment 800 can further include a variety of partiallycommunicating legacy appliances 842, such as infrared (“IR”) controlledwall air conditioners or other IR-controlled devices, which can becontrolled by IR signals provided by the hazard detectors 804 or thesmart wall switches 808.

According to embodiments, the smart thermostats 802, the hazarddetectors 804, the smart doorbells 806, the smart wall switches 808, thesmart wall plugs 810, and other devices of the smart-home environment800 are modular and can be incorporated into older and new houses. Forexample, the devices are designed around a modular platform consistingof two basic components: a head unit and a back plate, which is alsoreferred to as a docking station. Multiple configurations of the dockingstation are provided so as to be compatible with any home, such as olderand newer homes. However, all of the docking stations include a standardhead-connection arrangement, such that any head unit can be removablyattached to any docking station. Thus, in some embodiments, the dockingstations are interfaces that serve as physical connections to thestructure and the voltage wiring of the homes, and the interchangeablehead units contain all of the sensors, processors, user interfaces, thebatteries, and other functional components of the devices.

The smart-home environment 800 may also include communication withdevices outside of the physical home, but within a proximategeographical range of the home. For example, the smart-home environment800 may include a pool heater monitor 814 that communicates a currentpool temperature to other devices within the smart-home environment 800or receives commands for controlling the pool temperature. Similarly,the smart-home environment 800 may include an irrigation monitor 816that communicates information regarding irrigation systems within thesmart-home environment 800 and/or receives control information forcontrolling such irrigation systems. According to embodiments, analgorithm is provided for considering the geographic location of thesmart-home environment 800, such as based on the zip code or geographiccoordinates of the home. The geographic information is then used toobtain data helpful for determining optimal times for watering; suchdata may include sun location information, temperature, due point, soiltype of the land on which the home is located, etc.

By virtue of network connectivity, one or more of the smart-home devicesof FIG. 8 can further allow a user to interact with the device even ifthe user is not proximate to the device. For example, a user cancommunicate with a device using a computer (e.g., a desktop computer,laptop computer, or tablet) or other portable electronic device (e.g., asmartphone) 866. A webpage or app can be configured to receivecommunications from the user and control the device based on thecommunications and/or to present information about the device'soperation to the user. For example, the user can view a current setpointtemperature for a device and adjust it, using a computer. The user canbe in the structure during this remote communication or outside thestructure.

As discussed, users can control and interact with the smart thermostat,hazard detectors 804, and other smart devices in the smart-homeenvironment 800 using a network-connected computer or portableelectronic device 866. In some examples, some or all of the occupants(e.g., individuals who live in the home) can register their device 866with the smart-home environment 800. Such registration can be made at acentral server to authenticate the occupant and/or the device as beingassociated with the home and to give permission to the occupant to usethe device to control the smart devices in the home. An occupant can usehis registered device 866 to remotely control the smart devices of thehome, such as when the occupant is at work or on vacation. The occupantmay also use his registered device to control the smart devices when theoccupant is actually located inside the home, such as when the occupantis sitting on a couch inside the home. It should be appreciated that,instead of or in addition to registering devices 866, the smart-homeenvironment 800 makes inferences about which individuals live in thehome and are therefore occupants and which devices 866 are associatedwith those individuals. As such, the smart-home environment “learns” whois an occupant and permits the devices 866 associated with thoseindividuals to control the smart devices of the home.

In some embodiments, in addition to containing processing and sensingcapabilities, each of the devices 802, 804, 806, 808, 810, 812, 814, and816 (collectively referred to as “the smart devices”) is capable of datacommunications and information sharing with any other of the smartdevices, as well as to any central server or cloud-computing system orany other device that is network-connected anywhere in the world. Therequired data communications can be carried out using any of a varietyof custom or standard wireless protocols (Wi-Fi, ZigBee, 6LoWPAN, etc.)and/or any of a variety of custom or standard wired protocols (CAT6Ethernet, HomePlug, etc.).

According to embodiments, all or some of the smart devices can serve aswireless or wired repeaters. For example, a first one of the smartdevices can communicate with a second one of the smart devices via awireless router 860. The smart devices can further communicate with eachother via a connection to a network, such as the Internet 899. Throughthe Internet 899, the smart devices can communicate with acloud-computing system 864, which can include one or more centralized ordistributed server systems. The cloud-computing system 864 can beassociated with a manufacturer, support entity, or service providerassociated with the device. For one embodiment, a user may be able tocontact customer support using a device itself rather than needing touse other communication means such as a telephone or Internet-connectedcomputer. Further, software updates can be automatically sent fromcloud-computing system 864 to devices (e.g., when available, whenpurchased, or at routine intervals).

According to embodiments, the smart devices combine to create a meshnetwork of spokesman and low-power nodes in the smart-home environment800, where some of the smart devices are “spokesman” nodes and othersare “low-powered” nodes. Some of the smart devices in the smart-homeenvironment 800 are battery powered, while others have a regular andreliable power source, such as by connecting to wiring (e.g., to 120Vline voltage wires) behind the walls 854 of the smart-home environment.The smart devices that have a regular and reliable power source arereferred to as “spokesman” nodes. These nodes are equipped with thecapability of using any wireless protocol or manner to facilitatebidirectional communication with any of a variety of other devices inthe smart-home environment 800 as well as with the cloud-computingsystem 864. On the other hand, the devices that are battery powered arereferred to as “low-power” nodes. These nodes tend to be smaller thanspokesman nodes and can only communicate using wireless protocols thatrequire very little power, such as Zigbee, 6LoWPAN, etc. Further, some,but not all, low-power nodes are incapable of bidirectionalcommunication. These low-power nodes send messages, but they are unableto “listen”. Thus, other devices in the smart-home environment 800, suchas the spokesman nodes, cannot send information to these low-powernodes.

As described, the smart devices serve as low-power and spokesman nodesto create a mesh network in the smart-home environment 800. Individuallow-power nodes in the smart-home environment regularly send outmessages regarding what they are sensing, and the other low-powerednodes in the smart-home environment—in addition to sending out their ownmessages—repeat the messages, thereby causing the messages to travelfrom node to node (i.e., device to device) throughout the smart-homeenvironment 800. The spokesman nodes in the smart-home environment 800are able to “drop down” to low-powered communication protocols toreceive these messages, translate the messages to other communicationprotocols, and send the translated messages to other spokesman nodesand/or cloud-computing system 864. Thus, the low-powered nodes usinglow-power communication protocols are able to send messages across theentire smart-home environment 800 as well as over the Internet 899 tocloud-computing system 864. According to embodiments, the mesh networkenables cloud-computing system 864 to regularly receive data from all ofthe smart devices in the home, make inferences based on the data, andsend commands back to one of the smart devices to accomplish some of thesmart-home objectives described herein.

As described, the spokesman nodes and some of the low-powered nodes arecapable of “listening.” Accordingly, users, other devices, andcloud-computing system 864 can communicate controls to the low-powerednodes. For example, a user can use the portable electronic device (e.g.,a smartphone) 866 to send commands over the Internet 899 tocloud-computing system 864, which then relays the commands to thespokesman nodes in the smart-home environment 800. The spokesman nodesdrop down to a low-power protocol to communicate the commands to thelow-power nodes throughout the smart-home environment, as well as toother spokesman nodes that did not receive the commands directly fromthe cloud-computing system 864.

An example of a low-power node is a smart nightlight 870. In addition tohousing a light source, the smart nightlight 870 houses an occupancysensor, such as an ultrasonic or passive IR sensor, and an ambient lightsensor, such as a photodiode, photoresistor, phototransistor, or asingle-pixel sensor that measures light in the room. In someembodiments, the smart nightlight 870 is configured to activate thelight source when its ambient light sensor detects that the room is darkand when its occupancy sensor detects that someone is in the room. Inother embodiments, the smart nightlight 870 is simply configured toactivate the light source when its ambient light sensor detects that theroom is dark. Further, according to embodiments, the smart nightlight870 includes a low-power wireless communication chip (e.g., ZigBee chip)that regularly sends out messages regarding the occupancy of the roomand the amount of light in the room, including instantaneous messagescoincident with the occupancy sensor detecting the presence of a personin the room. As mentioned above, these messages may be sent wirelessly,using the mesh network, from node to node (i.e., smart device to smartdevice) within the smart-home environment 800 as well as over theInternet 899 to cloud-computing system 864.

Other examples of low-powered nodes include battery-operated versions ofthe hazard detectors 804. These hazard detectors 804 are often locatedin an area without access to constant and reliable (e.g., structural)power and, as discussed in detail below, may include any number and typeof sensors, such as smoke/fire/heat sensors, carbon monoxide/dioxidesensors, occupancy/motion sensors, ambient light sensors, flamedetectors, air quality sensors (e.g., for VOCs, particulate matter(e.g., PM 2.5), allergens, and other unhealthy contaminants such asNOx), temperature sensors, humidity sensors, and the like. Furthermore,hazard detectors 804 can send messages that correspond to each of therespective sensors to the other devices and cloud-computing system 864,such as by using the mesh network as described above.

Examples of spokesman nodes include smart doorbells 806, smartthermostats 802, smart wall switches 808, and smart wall plugs 810.These devices 802, 806, 808, and 810 are often located near andconnected to a reliable power source, and therefore can include morepower-consuming components, such as one or more communication chipscapable of bidirectional communication in any variety of protocols.

In some embodiments, the mesh network of low-powered and spokesman nodescan be used to provide exit lighting in the event of an emergency. Insome instances, to facilitate this, users provide pre-configurationinformation that indicates exit routes in the smart-home environment800. For example, for each room in the house, the user provides a map ofthe best exit route. It should be appreciated that instead of a userproviding this information, cloud-computing system 864 or some otherdevice could automatically determine the routes using uploaded maps,diagrams, architectural drawings of the smart-home house, as well asusing a map generated based on positional information obtained from thenodes of the mesh network (e.g., positional information from the devicesis used to construct a map of the house). In operation, when an alarm isactivated (e.g., when one or more of the hazard detector 804 detectssmoke and activates an alarm), cloud-computing system 864 or some otherdevice uses occupancy information obtained from the low-powered andspokesman nodes to determine which rooms are occupied and then turns onlights (e.g., smart nightlights 870, wall switches 808, smart wall plugs810 that power lamps, etc.) along the exit routes from the occupiedrooms so as to provide emergency exit lighting.

Further included and illustrated in the exemplary smart-home environment800 of FIG. 8 are service robots 862 each configured to carry out, in anautonomous manner, any of a variety of household tasks. For someembodiments, the service robots 862 can be respectively configured toperform floor sweeping, floor washing, etc. in a manner similar to thatof known commercially available devices such as the Roomba™ and Scooba™products sold by iRobot, Inc. of Bedford, Mass. Tasks such as floorsweeping and floor washing can be considered as “away” or “while-away”tasks for purposes of the instant description, as it is generally moredesirable for these tasks to be performed when the occupants are notpresent. For other embodiments, one or more of the service robots 862are configured to perform tasks such as playing music for an occupant,serving as a localized thermostat for an occupant, serving as alocalized air monitor/purifier for an occupant, serving as a localizedbaby monitor, serving as a localized hazard detector for an occupant,and so forth, it being generally more desirable for such tasks to becarried out in the immediate presence of the human occupant. Forpurposes of the instant description, such tasks can be considered as“human-facing” or “human-centric” tasks.

When serving as a localized air monitor/purifier for an occupant, aparticular service robot 862 can be considered to be facilitating whatcan be called a “personal health-area network” for the occupant, withthe objective being to keep the air quality in the occupant's immediatespace at healthy levels. Alternatively or in conjunction therewith,other health-related functions can be provided, such as monitoring thetemperature or heart rate of the occupant (e.g., using finely remotesensors, near-field communication with on-person monitors, etc.). Whenserving as a localized hazard detector for an occupant, a particularservice robot 862 can be considered to be facilitating what can becalled a “personal safety-area network” for the occupant, with theobjective being to ensure there is no excessive carbon monoxide, smoke,fire, etc., in the immediate space of the occupant. Methods analogous tothose described above for personal comfort-area networks in terms ofoccupant identifying and tracking are likewise applicable for personalhealth-area network and personal safety-area network embodiments.

According to some embodiments, the above-referenced facilitation ofpersonal comfort-area networks, personal health-area networks, personalsafety-area networks, and/or other such human-facing functionalities ofthe service robots 862, are further enhanced by logical integration withother smart sensors in the home according to rules-based inferencingtechniques or artificial intelligence techniques for achieving betterperformance of those human-facing functionalities and/or for achievingthose goals in energy-conserving or other resource-conserving ways.Thus, for one embodiment relating to personal health-area networks, theair monitor/purifier service robot 862 can be configured to detectwhether a household pet is moving toward the currently settled locationof the occupant (e.g., using on-board sensors and/or by datacommunications with other smart-home sensors along with rules-basedinferencing/artificial intelligence techniques), and if so, the airpurifying rate is immediately increased in preparation for the arrivalof more airborne pet dander. For another embodiment relating to personalsafety-area networks, the hazard detector service robot 862 can beadvised by other smart-home sensors that the temperature and humiditylevels are rising in the kitchen, which is nearby the occupant's currentdining room location, and responsive to this advisory, the hazarddetector service robot 862 will temporarily raise a hazard detectionthreshold, such as a smoke detection threshold, under an inference thatany small increases in ambient smoke levels will most likely be due tocooking activity and not due to a genuinely hazardous condition.

FIG. 9 illustrates a network-level view of an extensible devices andservices platform 900 with which a plurality of smart-home environments,such as the smart-home environment 800 of FIG. 8, can be integrated. Theextensible devices and services platform 900 includes cloud-computingsystem 864. Each of the intelligent, network-connected devices 802, 804,806, 808, 810, 812, 814, and 816 from FIG. 8 may communicate withcloud-computing system 864. For example, a connection to the Internet899 can be established either directly (for example, using 3G/4Gconnectivity to a wireless carrier), through a hubbed network 912 (whichcan be a scheme ranging from a simple wireless router, for example, upto and including an intelligent, dedicated whole-home control node), orthrough any combination thereof.

Although in some examples provided herein, the devices and servicesplatform 900 communicates with and collects data from the smart devicesof smart-home environment 800 of FIG. 8, it should be appreciated thatthe devices and services platform 900 communicates with and collectsdata from a plurality of smart-home environments across the world. Forexample, cloud-computing system 864 can collect home data 902 from thedevices of one or more smart-home environments, where the devices canroutinely transmit home data or can transmit home data in specificinstances (e.g., when a device queries the home data 902). Thus, thedevices and services platform 900 routinely collects data from homesacross the world. As described, the collected home data 902 includes,for example, power consumption data, occupancy data, HVAC settings andusage data, carbon monoxide levels data, carbon dioxide levels data,volatile organic compounds levels data, sleeping schedule data, cookingschedule data, inside and outside temperature humidity data, televisionviewership data, inside and outside noise level data, etc.

Cloud-computing system 864 can further provide one or more services 904.The services 904 can include, e.g., software updates, customer support,sensor data collection/logging, remote access, remote or distributedcontrol, or use suggestions (e.g., based on collected home data 902 toimprove performance, reduce utility cost, etc.). Data associated withthe services 904 can be stored at cloud-computing system 864 andcloud-computing system 864 can retrieve and transmit the data at anappropriate time (e.g., at regular intervals, upon receiving a requestfrom a user, etc.).

As part of services 904, user accounts may be maintained by thecloud-computing system 864. The user account may store subscriptioninformation, billing information, registration information, userpreferences, and/or other data associated with various smart-homedevices, such as one or more hazard detectors, installed within astructure that is linked with a user account. Occasionally, attention ofa user to his or her user account may be requested. In response to aquery from hazard detector 950 (or other smart-home device), a messagemay be transmitted by the cloud-computing system 864 to hazard detector950 (which may represent any of the previously described hazarddetectors) indicating that a status output by hazard detector 950 shouldindicate that a user is requested to log in to his or her user account.Further detail regarding the requested log may be transmitted by service904 to hazard detector 950. For instance, the reason for the requestedlogin may be expired payment information (such as an expired creditcard). The user can request detail on a status output by hazard detector950, which may be presented to the user as a color and animation outputvia a light of hazard detector 950. The request for detail may be byperforming a gesture within the vicinity of hazard detector 950. Aspoken message may then be output by hazard detector 950 indicating thatthe user is requested to log in to his account and may also indicate thereason of the payment information needing to be updated. As such, astatus check performed by hazard detector 950 may not only check thestatus of hazard detector 950 itself, but also the state of aremotely-maintained user account.

As illustrated in FIG. 9, an embodiment of the extensible devices andservices platform 900 includes a processing engine 906, which can beconcentrated at a single server or distributed among several differentcomputing entities without limitation. The processing engine 906 caninclude computerized engines (e.g., software executed by hardware)configured to receive data from devices of smart-home environments(e.g., via the Internet or a hubbed network), to index the data, toanalyze the data and/or to generate statistics based on the analysis oras part of the analysis. The analyzed data can be stored as derived homedata 908.

Results of the analysis or statistics can thereafter be transmitted backto the device that provided home data used to derive the results, toother devices, to a server providing a webpage to a user of the device,or to other non-device entities. For example, use statistics, usestatistics relative to use of other devices, use patterns, and/orstatistics summarizing sensor readings can be generated by theprocessing engine 906 and transmitted. The results or statistics can beprovided via the Internet 899. In this manner, the processing engine 906can be configured and programmed to derive a variety of usefulinformation from the home data 902. A single server can include one ormore engines.

In some embodiments, to encourage innovation and research and toincrease products and services available to users, the devices andservices platform 900 exposes a range of application programminginterfaces (APIs) 910 to third parties, such as charities, governmentalentities (e.g., the Food and Drug Administration or the EnvironmentalProtection Agency), academic institutions (e.g., universityresearchers), businesses (e.g., providing device warranties or serviceto related equipment, targeting advertisements based on home data),utility companies, and other third parties. The APIs 910 may be coupledto and permit third-party systems to communicate with cloud-computingsystem 864, including the services 904, the processing engine 906, thehome data 902, and the derived home data 908. For example, the APIs 910allow applications executed by the third parties to initiate specificdata processing tasks that are executed by cloud-computing system 864,as well as to receive dynamic updates to the home data 902 and thederived home data 908.

Account alert engine may serve to determine whether a hazard detectorshould provide an indication that the user's account requires attention.For instance, account alert engine 905 may periodically assess the stateof a user's account, such as whether settings need updating, whetherpayment information is up-to-date, whether one or more messages arepending, whether payment is due, etc. If user attention is required,upon a request being received from a hazard detector and a look-up ofthe user's account being performed, account alert engine may respondwith an indication that the user account requires attention. Additionaldetail may also be provided such that if the user performs a gesture orotherwise requests additional detail, such detail can be provided, suchas via an auditory message. If user attention is not required, upon arequest being received from a hazard detector and a look-up of theuser's account being performed (e.g., by determining an accountassociated with the hazard detector from which the request wasreceived), account alert engine may respond with an indication that theuser account does not require attention.

FIG. 10 illustrates an abstracted functional view of the extensibledevices and services platform 900 of FIG. 9, with particular referenceto the processing engine 906 as well as devices, such as those of thesmart-home environment 800 of FIG. 8. Even though devices situated insmart-home environments will have an endless variety of differentindividual capabilities and limitations, they can all be thought of assharing common characteristics in that each of them is a data consumer1065 (DC), a data source 1066 (DS), a services consumer 1067 (SC), and aservices source 1068 (SS). Advantageously, in addition to providing theessential control information needed for the devices to achieve theirlocal and immediate objectives, the extensible devices and servicesplatform 900 can also be configured to harness the large amount of datathat is flowing out of these devices. In addition to enhancing oroptimizing the actual operation of the devices themselves with respectto their immediate functions, the extensible devices and servicesplatform 900 can be directed to “repurposing” that data in a variety ofautomated, extensible, flexible, and/or scalable ways to achieve avariety of useful objectives. These objectives may be predefined oradaptively identified based on, e.g., usage patterns, device efficiency,and/or user input (e.g., requesting specific functionality).

For example, FIG. 10 shows processing engine 906 as including a numberof paradigms 1071. Processing engine 906 can include a managed servicesparadigm 1071 a that monitors and manages primary or secondary devicefunctions. The device functions can include ensuring proper operation ofa device given user inputs, estimating that (e.g., and responding to aninstance in which) an intruder is or is attempting to be in a dwelling,detecting a failure of equipment coupled to the device (e.g., a lightbulb having burned out), implementing or otherwise responding to energydemand response events, or alerting a user of a current or predictedfuture event or characteristic. Processing engine 906 can furtherinclude an advertising/communication paradigm 1071 b that estimatescharacteristics (e.g., demographic information), desires and/or productsof interest of a user based on device usage. Services, promotions,products or upgrades can then be offered or automatically provided tothe user. Processing engine 906 can further include a social paradigm1071 c that uses information from a social network, provides informationto a social network (for example, based on device usage), and/orprocesses data associated with user and/or device interactions with thesocial network platform. For example, a user's status as reported to histrusted contacts on the social network could be updated to indicate whenhe is home based on light detection, security system inactivation ordevice usage detectors. As another example, a user may be able to sharedevice-usage statistics with other users. In yet another example, a usermay share HVAC settings that result in low power bills and other usersmay download the HVAC settings to their smart thermostat 802 to reducetheir power bills.

The processing engine 906 can include achallenges/rules/compliance/rewards paradigm 1071 d that informs a userof challenges, competitions, rules, compliance regulations and/orrewards and/or that uses operation data to determine whether a challengehas been met, a rule or regulation has been complied with and/or areward has been earned. The challenges, rules or regulations can relateto efforts to conserve energy, to live safely (e.g., reducing exposureto toxins or carcinogens), to conserve money and/or equipment life, toimprove health, etc. For example, one challenge may involve participantsturning down their thermostat by one degree for one week. Those thatsuccessfully complete the challenge are rewarded, such as by coupons,virtual currency, status, etc. Regarding compliance, an example involvesa rental-property owner making a rule that no renters are permitted toaccess certain owner's rooms. The devices in the room having occupancysensors could send updates to the owner when the room is accessed.

The processing engine 906 can integrate or otherwise utilize extrinsicinformation 1073 from extrinsic sources to improve the functioning ofone or more processing paradigms. Extrinsic information 1073 can be usedto interpret data received from a device, to determine a characteristicof the environment near the device (e.g., outside a structure that thedevice is enclosed in), to determine services or products available tothe user, to identify a social network or social-network information, todetermine contact information of entities (e.g., public-service entitiessuch as an emergency-response team, the police or a hospital) near thedevice, etc., to identify statistical or environmental conditions,trends or other information associated with a home or neighborhood, andso forth.

An extraordinary range and variety of benefits can be brought about by,and fit within the scope of, the described extensible devices andservices platform 900, ranging from the ordinary to the profound. Thus,in one “ordinary” example, each bedroom of the smart-home environment800 can be provided with a smart wall switch 808, a smart wall plug 810,and/or smart hazard detectors 804, all or some of which include anoccupancy sensor, wherein the occupancy sensor is also capable ofinferring (e.g., by virtue of motion detection, facial recognition,audible sound patterns, etc.) whether the occupant is asleep or awake.If a serious fire event is sensed, the remote security/monitoringservice or fire department is advised of how many occupants there are ineach bedroom, and whether those occupants are still asleep (or immobile)or whether they have properly evacuated the bedroom. While this is, ofcourse, a very advantageous capability accommodated by the describedextensible devices and services platform, there can be substantiallymore “profound” examples that can truly illustrate the potential of alarger “intelligence” that can be made available. By way of perhaps amore “profound” example, the same bedroom occupancy data that is beingused for fire safety can also be “repurposed” by the processing engine906 in the context of a social paradigm of neighborhood childdevelopment and education. Thus, for example, the same bedroom occupancyand motion data discussed in the “ordinary” example can be collected andmade available (properly anonymized) for processing in which the sleeppatterns of schoolchildren in a particular ZIP code can be identifiedand tracked. Localized variations in the sleeping patterns of theschoolchildren may be identified and correlated, for example, todifferent nutrition programs in local schools.

With reference to FIG. 11, an embodiment of a special-purpose computersystem 1100 is shown. For example, one or more intelligent components,processing system 110 and components thereof may be a special-purposecomputer system 1100. Such a special-purpose computer system 1100 may beincorporated as part of a hazard detector and/or any of the othercomputerized devices discussed herein, such as a remote server, smartthermostat, or network. The above methods may be implemented bycomputer-program products that direct a computer system to perform theactions of the above-described methods and components. Each suchcomputer-program product may comprise sets of instructions (codes)embodied on a computer-readable medium that direct the processor of acomputer system to perform corresponding actions. The instructions maybe configured to run in sequential order, or in parallel (such as underdifferent processing threads), or in a combination thereof. Afterloading the computer-program products on a general purpose computersystem 1126, it is transformed into the special-purpose computer system1100.

Special-purpose computer system 1100 comprises a computer 1102, amonitor 1106 coupled to computer 1102, one or more additional useroutput devices 1130 (optional) coupled to computer 1102, one or moreuser input devices 1140 (e.g., keyboard, mouse, track ball, touchscreen) coupled to computer 1102, an optional communications interface1150 coupled to computer 1102, a computer-program product 1105 stored ina tangible computer-readable memory in computer 1102. Computer-programproduct 1105 directs computer system 1100 to perform the above-describedmethods. Computer 1102 may include one or more processors 1160 thatcommunicate with a number of peripheral devices via a bus subsystem1190. These peripheral devices may include user output device(s) 1130,user input device(s) 1140, communications interface 1150, and a storagesubsystem, such as random access memory (RAM) 1170 and non-volatilestorage drive 1180 (e.g., disk drive, optical drive, solid state drive),which are forms of tangible computer-readable memory.

Computer-program product 1105 may be stored in non-volatile storagedrive 1180 or another computer-readable medium accessible to computer1102 and loaded into random access memory (RAM) 1170. Each processor1160 may comprise a microprocessor, such as a microprocessor from Intel®or Advanced Micro Devices, Inc.®, or the like. To supportcomputer-program product 1105, the computer 1102 runs an operatingsystem that handles the communications of computer-program product 1105with the above-noted components, as well as the communications betweenthe above-noted components in support of the computer-program product1105. Exemplary operating systems include Windows® or the like fromMicrosoft Corporation, Solaris® from Sun Microsystems, LINUX, UNIX, andthe like.

User input devices 1140 include all possible types of devices andmechanisms to input information to computer 1102. These may include akeyboard, a keypad, a mouse, a scanner, a digital drawing pad, a touchscreen incorporated into the display, audio input devices such as voicerecognition systems, microphones, and other types of input devices. Invarious embodiments, user input devices 1140 are typically embodied as acomputer mouse, a trackball, a track pad, a joystick, wireless remote, adrawing tablet, a voice command system. User input devices 1140typically allow a user to select objects, icons, text and the like thatappear on the monitor 1106 via a command such as a click of a button orthe like. User output devices 1130 include all possible types of devicesand mechanisms to output information from computer 1102. These mayinclude a display (e.g., monitor 1106), printers, non-visual displayssuch as audio output devices, etc.

Communications interface 1150 provides an interface to othercommunication networks, such as communication network 1195, and devicesand may serve as an interface to receive data from and transmit data toother systems, WANs and/or the Internet. Embodiments of communicationsinterface 1150 typically include an Ethernet card, a modem (telephone,satellite, cable, ISDN), a (asynchronous) digital subscriber line (DSL)unit, a FireWire® interface, a USB® interface, a wireless networkadapter, and the like. For example, communications interface 1150 may becoupled to a computer network, to a FireWire® bus, or the like. In otherembodiments, communications interface 1150 may be physically integratedon the motherboard of computer 1102, and/or may be a software program,or the like.

RAM 1170 and non-volatile storage drive 1180 are examples of tangiblecomputer-readable media configured to store data such ascomputer-program product embodiments of the present invention, includingexecutable computer code, human-readable code, or the like. Other typesof tangible computer-readable media include floppy disks, removable harddisks, optical storage media such as CD-ROMs, DVDs, bar codes,semiconductor memories such as flash memories, read-only-memories(ROMs), battery-backed volatile memories, networked storage devices, andthe like. RAM 1170 and non-volatile storage drive 1180 may be configuredto store the basic programming and data constructs that provide thefunctionality of various embodiments of the present invention, asdescribed above.

Software instruction sets that provide the functionality of the presentinvention may be stored in RAM 1170 and non-volatile storage drive 1180.These instruction sets or code may be executed by the processor(s) 1160.RAM 1170 and non-volatile storage drive 1180 may also provide arepository to store data and data structures used in accordance with thepresent invention. RAM 1170 and non-volatile storage drive 1180 mayinclude a number of memories including a main random access memory (RAM)to store instructions and data during program execution and a read-onlymemory (ROM) in which fixed instructions are stored. RAM 1170 andnon-volatile storage drive 1180 may include a file storage subsystemproviding persistent (non-volatile) storage of program and/or datafiles. RAM 1170 and non-volatile storage drive 1180 may also includeremovable storage systems, such as removable flash memory.

Bus subsystem 1190 provides a mechanism to allow the various componentsand subsystems of computer 1102 to communicate with each other asintended. Although bus subsystem 1190 is shown schematically as a singlebus, alternative embodiments of the bus subsystem may utilize multiplebusses or communication paths within the computer 1102.

FIGS. 12-18 represent various illumination states that may be output bya hazard detector, such as the hazard detectors and other smart-homedevices detailed herein. Such illumination states may involve variouscolors and animations. Synthesized or recorded spoken audio messages mayaccompany at least some of such illumination states as detailed in thecharts of FIGS. 12-18. The majority of the time, it can be expected thatno light of a hazard detector will be illuminated. When the light isilluminated, the hazard detector is conveying a message (other than iflight state 1203 is illuminated). States 1201 and 1202, which involveblue and green illumination, are illustrated in FIG. 12 and may bepresented during a set up process. State 1203 involves a conditionalillumination state, which can be referred to as a “path light” state.Such a state may be illuminated in response to motion and the brightnesslevel in an ambient environment of a hazard detector dropping below athreshold brightness level. States 1204 and 1205 represent pre-alarm(pre-alert or early warning) states and emergency (alert or alarm)states. State 1206 may be for a separate light of the hazard detectorthat is indicative of if a wired (e.g., non-battery) power source isconnected and available, such as a household's 120 V AC power supply.State 1207 may be used as part of a setup process. For instance,“[device]” may be replaced with a spoken indication of the brand name ofthe hazard detector. State 1208 may be presented when a user presses abutton to test the hazard detector. State 1209 may represent a statethat is indicative of a potential danger and may server as an earlywarning. For state 1209 (and other states having a similar designation),[room type] may be replaced with a spoken indication of the type of roomin which the hazard detector is installed. At the time of installation,a user may have specified to the hazard detector, such as via aselection menu, the type of room in which the hazard detector was beinginstalled. States 1210 and 1211 represent additional pre-alarm states.States 1212, 1213, and 1214 represent various alarm (alert) states.State 1215 may be output when a smoke hazard is clearing. State 1216 maybe output when a carbon monoxide hazard is clearing. States 1217, 1218,1219, 1220, 1221 represent states output in response to a status checkthat identifies a problem with the hazard detector. Such a state beingoutput may require one or more user actions to resolve.

Preferably, the voice advisories during emergency-level alerts areinterleaved in time during silent periods between loud, shrieking tonalalarm patterns, so as to comply with regulations such as National FireProtection Association (NFPA) and Underwriters Laboratories (UL)standards that require a maximum silence period between tonal alarmpatterns of 1.5 seconds (Ref UL2034, UL217, NFPA72 and NFPA720).

It should be understood that the above detailed illumination states andaudio messages are merely exemplary. In various other embodiments, thecolors, animations, definitions and/or audio messages may be modified.

In order to provide input to various embodiments of the hazard detectorsdetailed herein, it may be possible to perform a gesture to provideinput, which may result in silencing “nuisance” alarms—that is, alarmstriggered by a non-hazardous condition (e.g., burning toast). Within adistance of approximately 2-6 feet of the hazard detector, a wave of auser's hand and arm can be detected. In some embodiments, multiple wavesmust be performed for the gesture to be detected. As detailed inrelation to FIG. 19, some of the pre-alert or alert states may silenced,at least temporarily, by using a wave gesture. In some situations, asnoted in FIG. 19, certain situations preclude the alarm from beingsilenced. A wave gesture can also be used for canceling a manual testand/or to hear a detailed message when a visual status is beingpresented via illumination. In some embodiments, rather than performinga gesture, a user may push a button (or physically actuate some otherpart) of the hazard detector.

If multiple hazard detectors are present, all of the hazard detectorsmay output light and sound of a heads-up (pre-alert) or emergency(alert) situation is present. To silence an alarm (either in thepre-alert or alert state), the user may be required to perform thegesture (or push a button) at the hazard detector that originallydetected the hazard. Once the proper hazard detector is silenced, eachother hazard detector may be silenced (based on wireless communicationbetween the hazard detectors).

Referring to FIG. 20, an exemplary situation of when a heads-up(pre-alert) state is used. A gentle heads-up (pre-alert) warns a user ofa condition that has risen above normal, but has not yet triggered afull alert (emergency) state. Sounds and messages output during apre-alert state are intended to be less irritating and urgent thanmessages during an alert state. By having such a pre-alarm state, usersmay be less likely to disable a hazard detector and, thus, the hazarddetector may be more likely to be functioning when needed.

As an example, at point 2010, the hazard detector is monitoring itsambient environment for hazards, such as smoke and carbon monoxide. Anincreased level of carbon monoxide or smoke may be detected at point2020. At such point, a pre-alert message and illumination may be outputto warn users of the impending conditions. Such a pre-alert may involvea notable, but non jarring (in comparison to a shrieking emergency alarmsound), bell or ringing sound. The notable but non-jarring sound may besimilar in intensity to the bell sound emitted by an elevator whenarriving at the target floor, which is enough to notify but not so muchas to unpleasantly jar the user. A user may be permitted to silence sucha heads-up (pre-alert) message. At point 2030, a full alarm may besounded, which may involve a loud, shrill alarm sound. At point 2040, amessage (with an accompanying illumination state) may be outputindicative of normal conditions resuming. Heads-up (pre-alert) statesare associated with a yellow illumination state while emergency (alert)states are associated with red illumination states. If the hazard levelin the environment of the hazard detector rises quickly, no pre-alertstate may be entered by the hazard detector. Rather, the alarm state maybe directly entered from a monitoring state.

It should be noted that the methods, systems, and devices discussedabove are intended merely to be examples. It must be stressed thatvarious embodiments may omit, substitute, or add various procedures orcomponents as appropriate. For instance, it should be appreciated that,in alternative embodiments, the methods may be performed in an orderdifferent from that described, and that various steps may be added,omitted, or combined. Also, features described with respect to certainembodiments may be combined in various other embodiments. Differentaspects and elements of the embodiments may be combined in a similarmanner. Also, it should be emphasized that technology evolves and, thus,many of the elements are examples and should not be interpreted to limitthe scope of the invention.

Specific details are given in the description to provide a thoroughunderstanding of the embodiments. However, it will be understood by oneof ordinary skill in the art that the embodiments may be practicedwithout these specific details. For example, well-known, processes,structures, and techniques have been shown without unnecessary detail inorder to avoid obscuring the embodiments. This description providesexample embodiments only, and is not intended to limit the scope,applicability, or configuration of the invention. Rather, the precedingdescription of the embodiments will provide those skilled in the artwith an enabling description for implementing embodiments of theinvention. Various changes may be made in the function and arrangementof elements without departing from the spirit and scope of theinvention.

Also, it is noted that the embodiments may be described as a processwhich is depicted as a flow diagram or block diagram. Although each maydescribe the operations as a sequential process, many of the operationscan be performed in parallel or concurrently. In addition, the order ofthe operations may be rearranged. A process may have additional stepsnot included in the figure.

Having described several embodiments, it will be recognized by those ofskill in the art that various modifications, alternative constructions,and equivalents may be used without departing from the spirit of theinvention. For example, the above elements may merely be a component ofa larger system, wherein other rules may take precedence over orotherwise modify the application of the invention. Also, a number ofsteps may be undertaken before, during, or after the above elements areconsidered. Accordingly, the above description should not be taken aslimiting the scope of the invention.

What is claimed is:
 1. A method for detecting that a hazardous conditionis easing, the method comprising: measuring, by a hazard detector, afirst amount of the hazardous condition present in an ambientenvironment of the hazard detector; setting, by the hazard detector, amode of the hazard detector to a pre-alarm state based on the measuredfirst amount of the hazardous condition; measuring, by the hazarddetector, a second amount of the hazardous condition present in theambient environment of the hazard detector, wherein the second amount isless than the first amount; determining, by the hazard detector, basedon the second amount of the hazardous condition present in the ambientenvironment, to set the mode to a non-alarm state; and in response todetermining, at least partially based on the second amount of thehazardous condition present in the ambient environment to set the modeof the hazard detector to the non-alarm state from the pre-alarm stateor an alarm state, outputting an indication that the hazardous conditionhas eased, wherein: the hazardous condition having eased indicates thehazardous condition in the ambient environment of the hazard detectorhas decreased in amount.
 2. The method for detecting that the hazardouscondition is easing of claim 1, wherein the indication output comprisesan auditory message that comprises speech being output by a speaker ofthe hazard detector.
 3. The method for detecting that the hazardouscondition is easing of claim 2, further comprising: accessing, by thehazard detector, a stored indication of a location at which the hazarddetector is installed, wherein the auditory message comprises speechindicative of the location.
 4. The method for detecting that thehazardous condition is easing of claim 1, wherein the indication outputcomprises a light of the hazard detector outputting a color indicativeof the non-alarm state.
 5. The method for detecting that the hazardouscondition is easing of claim 1, further comprising: in response todetermining, at least partially based on the first amount of thehazardous condition present in the ambient environment to set the modeof the hazard detector to the pre-alarm state, outputting an indicationof the pre-alarm state comprising an auditory message.
 6. The method fordetecting that the hazardous condition is easing of claim 5, whereinoutputting the indication of the pre-alarm state comprising outputtingpulsing light of a color indicative of the pre-alarm state.
 7. Themethod for detecting that the hazardous condition is easing of claim 1,further comprising: measuring, by the hazard detector, a third amount ofthe hazardous condition present in the ambient environment of the hazarddetector, wherein the third amount is greater than the first amount andthe second amount; and determining, by the hazard detector, at leastpartially based on the third amount of the hazardous condition presentin the ambient environment, to set the mode to an alarm state, whereinthe alarm state causes an alarm of the hazard detector to be sounded. 8.The method for detecting that the hazardous condition is easing of claim1, further comprising: determining, by the hazard detector, that athreshold period of time has elapsed while an amount of hazardouscondition present in the ambient environment of the hazard detector hasremained below a stored hazardous condition value, wherein determiningto set the mode to a non-alarm state is further based on determining thethreshold period of time has elapsed while the amount of hazardouscondition present in the ambient environment of the hazard detector hasremained below the stored hazardous condition value.
 9. A hazarddetector comprising: a hazard sensor that measures amounts of ahazardous condition present in an ambient environment of the hazarddetector; an output component that outputs information; and a processingsystem that comprises one or more processors, the processing systembeing in communication with the output component and the hazard sensor,the processing system being configured to: receive a first measurementof a first amount of the hazardous condition present in an ambientenvironment of the hazard detector from the hazard sensor; set a mode ofthe hazard detector to a pre-alarm or alarm state based on the firstmeasurement; receive a second measurement of a second amount of thehazardous condition present in the ambient environment of the hazarddetector from the hazard sensor; determine, based on the secondmeasurement, to set the mode to a non-alarm state in response todetermining, at least partially based on the second amount of thehazardous condition present in the ambient environment to set the modeof the hazard detector to the non-alarm state from the alarm state orthe pre-alarm state, cause an indication that the hazardous conditionhas eased to be output by the output component, wherein the hazardouscondition having eased indicates the hazardous condition in the ambientenvironment of the hazard detector has dissipated.
 10. The hazarddetector of claim 9, wherein the indication output by the outputcomponent comprises an auditory message that comprises speech.
 11. Thehazard detector of claim 10, wherein the processing system is furtherconfigured to access a stored indication of a location at which thehazard detector is installed, wherein the auditory message comprisesspeech indicative of the location.
 12. The hazard detector of claim 9,wherein the indication output comprises a light of the output componentoutputting colored light indicative of the non-alarm state.
 13. Thehazard detector of claim 9, wherein the processing system is furtherconfigured to: in response to determining to set the mode of the hazarddetector to the pre-alarm state, cause an indication of the pre-alarmstate to be output by the output component, the indication comprising anauditory message.
 14. The hazard detector of claim 13, wherein theoutput device outputting the indication of the pre-alarm state comprisesthe output device outputting pulsing light of a color indicative of thepre-alarm state.
 15. The hazard detector of claim 9, wherein theprocessing system is further configured to: receive a third measurementof a third amount of the hazardous condition present in the ambientenvironment of the hazard detector from the hazard sensor, wherein thethird amount is greater than the first amount and the second amount; anddetermine, at least partially based on the third measurement, to set themode to an alarm state, wherein the alarm state causes an alarm of thehazard detector to be sounded.
 16. The hazard detector of claim 9,wherein the processing system is further configured to: determine that athreshold period of time has elapsed while an amount of the hazardouscondition, as measured by the hazard sensor, present in the ambientenvironment has remained below a stored hazardous condition value,wherein the one or more processors being configured to determine to setthe mode to a non-alarm state is further based on determining thethreshold period of time has elapsed while the amount of the hazardouscondition present in the ambient environment has remained below thestored hazardous condition value.
 17. A non-transitoryprocessor-readable medium for a hazard detector, comprisingprocessor-readable instructions configured to cause one or moreprocessors of the hazard detector to: receive a first measurement of afirst amount of the hazardous condition present in an ambientenvironment of the hazard detector from the hazard sensor; set a mode ofthe hazard detector to a pre-alarm or alarm state based on the firstmeasurement; receive a second measurement of a second amount of thehazardous condition present in the ambient environment of the hazarddetector from the hazard sensor; determine, based on the secondmeasurement, to set the mode to a non-alarm state; and in response todetermining at least partially based on the second measurement to setthe mode of the hazard detector to the non-alarm state, cause anindication that the hazardous condition has eased to be output by thehazard detector, wherein the hazardous condition having eased indicatesthe hazardous condition in the ambient environment of the hazarddetector has decreased in amount.
 18. The non-transitoryprocessor-readable medium for the hazard detector of claim 17, furthercomprising: accessing a stored indication of a room in which the hazarddetector is located, wherein causing the indication that the hazardouscondition has eased comprises outputting an auditory message indicativeof the room.